עיבור השנה וקידוש החודש

ת"ר אין מעברין את השנה אלא אם כן ירצה נשיא ומעשה ברבן גמליאל שהלך ליטול רשות אצל שלטון אחד שבסוריא ושהה לבא ועיברו את השנה על מנת שירצה רבן גמליאל וכשבא ר"ג ואמר רוצה אני נמצאת שנה מעוברת תנו רבנן אין מעברין את השנה אלא אם כן היתה צריכה מפני הדרכים ומפני הגשרים ומפני תנורי פסחים ומפני גליות ישראל שנעקרו ממקומן ועדיין לא הגיעו אבל לא מפני השלג ולא מפני הצינה ולא מפני גליות ישראל שלא עקרו ממקומן ת"ר אין מעברין את השנה לא מפני הגדיים ולא מפני הטלאים ולא מפני הגוזלות שלא פירחו אבל עושין אותן סעד לשנה כיצד רבי ינאי אומר משום רבן שמעון בן גמליאל מהודעין אנחנא לכון דגוזליא רכיכין ואימריא דערקין וזימנא דאביבא לא מטא ושפרת מילתא באנפאי ואוסיפית על שתא דא תלתין יומין מיתיבי כמה עיבור השנה שלשים יום רבן שמעון בן גמליאל אומר חדש אמר רב פפא רצו חדש רצו שלשים יום

Sanhedrin 11a

by those who were invited by the Nasi, the president of the Great Sanhedrin, for that purpose. There was an incident involving Rabban Gamliel, who said to the Sages: Bring me seven of the Sages early tomorrow morning to the loft designated for convening a court to intercalate the year. He went to the loft early the next morning and found eight Sages there. Rabban Gamliel said: Who is it who ascended to the loft without permission? He must descend immediately. Shmuel HaKatan stood up and said: I am he who ascended without permission; and I did not ascend to participate and be one of those to intercalate the year, but rather I needed to observe in order to learn the practical halakha. Rabban Gamliel said to him: Sit, my son, sit. It would be fitting for all of the years to be intercalated by you, as you are truly worthy. But the Sages said: The year may be intercalated only by those who were invited for that purpose. The Gemara notes: And it was not actually Shmuel HaKatan who had come uninvited, but another person. And due to the embarrassment of the other, Shmuel HaKatan did this, so that no one would know who had come uninvited. The Gemara relates that the story about Shmuel HaKatan is similar to an incident that occurred when Rabbi Yehuda HaNasi was sitting and teaching, and he smelled the odor of garlic. Rabbi Yehuda HaNasi was very sensitive and could not tolerate this odor. He said: Whoever ate garlic should leave. Rabbi Ḥiyya stood up and left. Out of respect for Rabbi Ḥiyya, all of those in attendance stood up and left. The next day, in the morning, Rabbi Shimon, son of Rabbi Yehuda HaNasi, found Rabbi Ḥiyya, and he said to him: Are you the one who disturbed my father by coming to the lecture with the foul smell of garlic? Rabbi Ḥiyya said to him: There should not be such behavior among the Jewish people. I would not do such a thing, but I assumed the blame and left so that the one who did so would not be embarrassed. And from where did Rabbi Ḥiyya learn that characteristic of being willing to implicate himself in order to save someone else from being embarrassed? He learned it from Rabbi Meir, as it is taught in a baraita: There was an incident involving a certain woman who came to the study hall of Rabbi Meir. She said to him: My teacher, one of you, i.e., one of the men studying in this study hall, betrothed me through intercourse. The woman came to Rabbi Meir to appeal for help in identifying the man, so that he would either marry her or grant her a divorce. As he himself was also among those who studied in the study hall, Rabbi Meir arose and wrote her a bill of divorce, and he gave it to her. Following his example, all those in the study hall arose and wrote bills of divorce and gave them to her. In this manner, the right man also gave her a divorce, freeing her to marry someone else. And from where did Rabbi Meir learn that characteristic? From Shmuel HaKatan, in the incident outlined above. And from where did Shmuel HaKatan learn it? From Shecaniah ben Jehiel, as it is written: “And Shecaniah, the son of Jehiel, one of the sons of Elam, answered and said to Ezra: We have broken faith with our God, and have married foreign women of the peoples of the land; yet now there is hope for Israel concerning this” (Ezra 10:2). And although he confessed, Shecaniah is not listed among those who took foreign wives (Ezra 10:18–44). Evidently, he confessed only to spare the others from public embarrassment. The Gemara continues: And from where did Shecaniah ben Jehiel learn it? From an incident involving Joshua, as it is written: “And the Lord said to Joshua: Get yourself up; why do you fall upon your face? Israel has sinned” (Joshua 7:10–11). Joshua said before Him: Master of the Universe, who sinned? God said to him: And am I your informer? Rather, cast lots to determine who is guilty. In this way, God did not directly disclose the identity of the sinner to Joshua. And if you wish, say instead that Shecaniah ben Jehiel learned this from an incident involving Moses, as it is written: “And the Lord said to Moses: How long do you refuse to keep My mitzvot and My laws?” (Exodus 16:28). Although only a small number of people attempted to collect the manna on Shabbat, God spoke as though the entire nation were guilty, so as not to directly expose the guilty. § Since Shmuel HaKatan and his great piety were mentioned, the Gemara now relates several incidents that shed additional light on his personality. The Sages taught: After the last of the prophets, Haggai, Zechariah, and Malachi, died, the Divine Spirit of prophetic revelation departed from the Jewish people. But nevertheless, they were still utilizing a Divine Voice, which they heard as a kind of echo of prophecy. One time, a group of Sages were reclining in the loft of the house of Gurya in Jericho, and a Divine Voice was bestowed upon them from Heaven, saying: There is one here who is fit for the Divine Presence to rest upon him as it rested upon Moses our teacher, but his generation is not deserving of this distinction. The Sages set their eyes upon Hillel the Elder, trusting that he was the one indicated by the Divine Voice. And when he died, the Sages said about him: Alas, the pious man, alas, the humble man, a disciple of Ezra. The baraita continues: Another time, a group of Sages were reclining in the loft in Yavne, and a Divine Voice was bestowed upon them from Heaven, saying: There is one here who is fit for the Divine Presence to rest upon him in prophecy, but his generation is not deserving of this distinction. The Sages set their eyes upon Shmuel HaKatan. And when he died, the Sages said about him: Alas, the pious man, alas, the humble man, a disciple of Hillel. Additionally, he said at the time of his death, under the influence of the Divine Spirit: Rabban Shimon ben Gamliel, the Nasi of the Great Sanhedrin, and Rabbi Yishmael, the High Priest, will die by the sword, and their friends will die by other executions, and the rest of the nation will be despoiled, and great troubles will ultimately come upon the world. And they also wished to say thus: Alas, the pious man, alas, the humble man, about Yehuda ben Bava, in their eulogy for him, but the hour was torn, i.e., the opportunity was lost, as one does not eulogize those executed by the government. As will be explained (14a), Yehuda ben Bava was executed by the government. § The Gemara returns to the discussion about intercalation of the year. The Sages taught: The year may be intercalated only if the Nasi of the Sanhedrin wants to intercalate it. And there was once an incident involving Rabban Gamliel, who went to ask permission for some communal matter from an officer [hegmon] in Syria, and he tarried in returning until after it was too late to intercalate the year. And because they did not know what his opinion on the matter was, they intercalated the year on the condition that Rabban Gamliel would want to do so. And when Rabban Gamliel came back and said: I want to intercalate the year, the year was found to be retroactively intercalated. The Sages taught: The year may be intercalated only if it is necessary due to damage to the roads, if the rain has damaged them in such a way that they are inaccessible for those ascending to Jerusalem for Passover; or due to the bridges that are likewise in disrepair; or due to the ovens for the Paschal offerings that are damaged and unfit for roasting the offerings; or due to the Diaspora Jews who have left their homes and still have not arrived due to delays in travel. But the year may not be intercalated due to the snow, and not due to the cold, and not due to the Diaspora Jews who have not yet left from their homes, even if they no longer have enough time to reach Jerusalem for the Festival. The Sages taught: The year may not be intercalated due to the young goats and not due to the lambs, to allow them to grow larger before they are to be sacrificed as Paschal offerings; and not due to the fledgling doves who have not yet developed sufficiently to fly, so that there won’t be enough of them to supply all those who wish to bring bird offerings at the Festival. But all these considerations may be made supporting factors in the decision to intercalate the year. The Gemara asks: How so? Rabbi Yannai says in the name of Rabban Shimon ben Gamliel, i.e., this is the language Rabban Shimon ben Gamliel used in his declaration of the intercalation: We are notifying you that the fledglings are tender, and that the lambs are thin [de’arkin], and time for the spring has not yet arrived. And consequently, the matter is good in my eyes, and I have therefore added thirty days onto this year. The Gemara raises an objection to the report that Rabban Shimon ben Gamliel holds the intercalated month is thirty days long. It is taught in a baraita: How long is the additional month in an intercalated leap year? The Rabbis say: Thirty days. Rabban Shimon ben Gamliel says: A standard month, which is twenty-nine days long. What, then, does Rabban Shimon ben Gamliel hold? Rav Pappa said: Rabban Gamliel holds that if the court wants, it may add a standard month, and if it wants, it may add a month of thirty days. Concerning the declaration of Rabban Shimon ben Gamliel, the Gemara observes: Come and see what difference there is between

סנהדרין י״א ב

תנו רבנן על שלשה דברים מעברין את השנה על האביב ועל פירות האילן ועל התקופה על שנים מהן מעברין ועל אחד מהן אין מעברין ובזמן שאביב אחד מהן הכל שמחין רבי שמעון בן גמליאל אומר על התקופה איבעיא להו על התקופה שמחין או על התקופה מעברין תיקו: ת"ר על שלשה ארצות מעברין את השנה יהודה ועבר הירדן והגליל על שתים מהן מעברין ועל אחת מהן אין מעברין ובזמן שיהודה אחת מהן הכל שמחין שאין עומר בא אלא מיהודה ת"ר אין מעברין את השנים אלא ביהודה ואם עיברוה בגליל מעוברת העיד חנניה איש אונו אם עיברוה בגליל אינה מעוברת א"ר יהודה בריה דרבי שמעון בן פזי מאי טעמא דחנניה איש אונו אמר קרא (דברים יב, ה) לשכנו תדרשו ובאת שמה כל דרישה שאתה דורש לא יהיו אלא בשכנו של מקום

ת"ר אין מעברין את השנה

Sanhedrin 11b

the earlier, stern authorities and the later, humble authorities, for although Rabban Shimon ben Gamliel was known as particularly humble, his proclamation was written with less modesty than that of his father, Rabban Gamliel, who was known to be particularly stern. As it is taught in a baraita (Tosefta 2:6): There was an incident involving Rabban Gamliel, who was sitting on a step on the Temple Mount, and Yoḥanan, that scribe, was standing before him, and three blank documents cut from parchment and ready for writing were set before him. Rabban Gamliel said to the scribe: Take one document, and write: To our brothers, the people of the Upper Galilee, and to our brothers, the people of the Lower Galilee, may your peace increase. We are informing you that the time has come for eradication of tithes that had been separated from produce but not yet given to their designated recipients, as is to be done in the fourth and seventh years of the Sabbatical-Year cycle, to separate the tithe from the vat of olives, because most of the local olives were grown in the Galilee. Rabban Gamliel continued, instructing the scribe: And take one document, and write: To our brothers, the people of the South, meaning the area of Judea and its environs, may your peace increase. We are informing you that the time has come for eradication, to separate the tithe from the mounds of stalks of grains, because most of the local grain was grown in the Judea region. Rabban Gamliel continued to instruct the scribe: And take one document, and write: To our brothers, the people of the Diaspora in Babylonia, and to our brothers who are in Medea, and to the rest of the entire Jewish Diaspora, may your peace increase forever. We are informing you that the fledglings are tender, and the lambs are thin, and time for the spring has not come. And consequently, the matter is good before me and before my colleagues, i.e., in our estimation, and I have consequently added thirty days to this year. The third letter indicates that evidently Rabban Gamliel included others in his decision. The Gemara rejects this, and explains: Perhaps this incident occurred after they deposed Rabban Gamliel from his position as Nasi. When he was reinstated, he shared his office with Rabbi Elazar ben Azarya. Therefore, he wrote the decision in the name of his colleagues as well. § The Sages taught in a baraita (Tosefta 2:2): The court may intercalate the year for three matters: For the ripening of the grain, if it is not yet time for the barley to ripen; for the fruit of the trees, if they have not yet ripened; and for the equinox, i.e., to ensure that the autumnal equinox will precede Sukkot. If two of these concerns apply, the court intercalates the year even if the third factor does not apply; but for only one of them the court does not intercalate the year. The baraita continues: And when the ripening of the grain is one of the concerns, everyone is happy. Since the grain is not yet ripe, the people do not mind waiting an extra month for Nisan. If the grain is already ripe, however, the extra month would simply prolong the period during which the grain may not be eaten due to the prohibition of the new crop, as the new crop may be harvested and eaten only after the sacrifice of the omer offering on the sixteenth of Nisan (see Leviticus 23:14). Rabban Shimon ben Gamliel says: For the equinox. The Gemara seeks to clarify this statement: A dilemma was raised before the Sages. When he said: For the equinox, did he mean this is the reason that everyone is happy, or did he mean that only for the equinox may the court intercalate the year? The dilemma shall stand unresolved. The Sages taught in a baraita (Tosefta 2:2): The court may intercalate the year for three regional lands of Eretz Yisrael, meaning that the court considers the agricultural situation in three regions: Judea, and Transjordan, and the Galilee. If there is a concern about two of them, the court intercalates the year even if the third region does not need it, but if there is a concern about only one of them the court does not intercalate the year. And when Judea is one of them, everyone is happy, because the omer offering comes only from Judea. If the court therefore ensures that the crops in Judea ripen just before the omer is brought, the crops will certainly be ripe in the other regions as well, and there will be no complications with the prohibition of the new crop. § The Sages taught in a baraita (Tosefta 2:2): The court may intercalate the years only when located in Judea. And if they intercalated it when located in the Galilee, the year is nevertheless intercalated. Ḥananya of Ono testified: Even if the court already formally intercalated the year when located in the Galilee, it is not intercalated. Rabbi Yehuda, son of Rabbi Shimon ben Pazi, says: What is the reasoning of Ḥananya of Ono? The verse states: “But to the place that the Lord your God shall choose out of all your tribes to put His name there, to His abode shall you seek, and there you shall come” (Deuteronomy 12:5). This is interpreted as: Every pursuit that you shall pursue in the area of halakha must be only in the abode of the Omnipresent, in close proximity to Jerusalem, i.e., in Judea. The Sages taught in a baraita (Tosefta 2:7): The court may intercalate the year only during the day; and if the court intercalated it at night, it is not intercalated. And the court may sanctify the month only during the day; and if the court sanctified it at night, it is not sanctified. Rav Abba says: What is the verse from which this halakha is derived? “Sound the shofar at the New Moon, at the concealed time for our Festival day” (Psalms 81:4). On which Festival is the new moon concealed? You must say it is Rosh HaShana, which occurs on the first of the month, before the moon is visible, whereas the moon is visible during the other Festivals, which occur later in the month. And it is written in the next verse: “For it is a statute for Israel, a judgment of the God of Jacob” (Psalms 81:5). Just as all civil judgment is done during the day, so too is the sanctification of Rosh HaShana, and the sanctification of the month in general, done during the day. The Sages taught in a baraita (Tosefta 2:5): The court does not intercalate the year

סנהדרין י״ב א

בשני רעבון תניא רבי אומר (מלכים ב ד, מב) ואיש בא מבעל שלישה ויבא לאיש האלהים לחם בכורים עשרים לחם שעורים וגו' ואין לך קלה בכל ארץ ישראל לבשל פירותיה יותר מבעל שלישה ואף על פי כן לא בכרה אלא מין אחד שמא תאמר חטים תלמוד לומר שעורים שמא תאמר לפני העומר תלמוד לומר (מלכים ב ד, מב) תן לעם ויאכלו אחר העומר היה אמור מעתה ראויה היתה אותה שנה שתתעבר ומפני מה לא עיברה אלישע ששנת בצורת היתה והיו הכל רצין לבית הגרנות

Sanhedrin 12a

during years of famine. When grain is scarce, intercalating the year would exacerbate the food shortage by delaying the omer offering, which is brought in Nisan, thereby prolonging the period during which the new crop is forbidden. It is taught in a baraita: Rabbi Yehuda HaNasi says that this principle can be demonstrated based on an incident related in the Bible. The verse states with regard to the prophet Elisha: “And there came a man from Ba’al Shalisha, and he brought to the man of God bread of the first fruits, twenty loaves of barley, and fresh ears of corn in his sack. And he said: Give to the people, that they may eat” (II Kings 4:42). The incident is analyzed: You do not have in all of Eretz Yisrael an environment in which fruit ripens more swiftly than in Ba’al Shalisha, and even so, only one of the seven species had ripened at that time, as the verse testifies that he brought him “bread of the first fruits.” Lest you say the verse speaks of wheat, which ripens close to the time of the festival of Shavuot, the verse states “barley.” Lest you say that the incident took place before the omer offering was sacrificed, the verse states: “Give to the people, that they may eat.” As they were permitted to eat, it must be that the incident was after the omer offering was brought. Based on this, say that even in the place in which fruit ripened the fastest in all of Eretz Yisrael, after the omer had been brought, only the barley had ripened. Evidently, the year was fit to be intercalated, because the spring produce was not sufficiently mature in time. And for what reason did the prophet Elisha not intercalate it? Because it was a year of scarcity, as described in the Bible (see II Kings 4:38), and everyone was running to the granary. Intercalating the year would have made it even more difficult to obtain produce. § The Sages taught in a baraita (Tosefta 2:3): The court may not intercalate the year before Rosh HaShana. And if the court intercalated it this early, it is not intercalated. But if there was a need to intercalate it early due to exigent circumstances, e.g., religious persecution, they may intercalate it immediately after Rosh HaShana. Even so, they may intercalate it only by adding a second month of Adar. The Gemara asks: Is that so, that intercalation may be determined only after Rosh HaShana? But the Sages of Eretz Yisrael sent the following encoded message to Rava during the time of Roman persecution: A pair of Torah scholars came from Rakkath, the biblical name for Tiberias (see Joshua 19:35), which was the seat of the Sanhedrin in Rava’s time. They meant to reach the Diaspora community, but the pair was apprehended by the eagle, i.e., Roman soldiers, whose symbol was the eagle; and in their possession were precious items made in Luz. The Gemara interrupts the story to explain: And what are those items from Luz? Sky-blue dye, which is necessary for ritual fringes. The message continued: In the merit of divine mercy and in their merit, they were spared execution and emerged in peace. Nevertheless, they did not reach their destination. The message continued: And the offspring of Nahshon, meaning the Sages of the court of the Nasi, who was descended from the prince of Judah, Nahshon ben Amminadab (see Numbers 7:12), sought to establish a pillar, i.e., they sought to add a month to the year. But that Edomite, the local Roman governor, did not allow them to intercalate the year. Nevertheless, the members of the assembly gathered, and they established a pillar, in the month in which Aaron the priest died, i.e., the Sages of Eretz Yisrael convened in the month of Av, which is before Rosh HaShana, and determined that the following year should be intercalated. Evidently, then, in exigent circumstances, intercalation may be done even before Rosh HaShana. The Gemara answers: The court may calculate the need for an extra month even before Rosh HaShana, but they may not reveal and publicize the decision until after Rosh HaShana. The Gemara asks about the language of the coded message. From where may it be inferred that this word pillar [netziv] is a term for the month? As it is written: “And Solomon had twelve officers [netzivim] over all Israel, and they provided for the king and his household for a month in the year” (I Kings 4:7). This indicates that each netziv was responsible for a particular month. Once this verse was quoted, the Gemara inquires: But isn’t it written afterward: “And one officer that was in the land” (I Kings 4:19), indicating that there were more than twelve netzivim? Rav Yehuda and Rav Naḥman offer answers. One says: One officer was appointed over all of the others. And one says: The extra officer corresponded to the intercalated month. If the year had an additional month, he was responsible for the king’s provisions during that month. § The Sages taught in a baraita (Tosefta 2:4): The court may not intercalate the year from one year to another, and it does not intercalate three successive years, one directly after the other. Rabbi Shimon says: There was an incident involving Rabbi Akiva at the time when he was incarcerated in prison, and he intercalated three years, one after the other. The Sages said to Rabbi Shimon: Is there any proof from there? Rabbi Akiva merely made the calculations, but a special court sat and established each one at its time. The Sages taught in a baraita (Tosefta 2:5): The court may not intercalate the year in the Sabbatical Year, so as not to prolong the prohibitions of the Sabbatical Year, nor in the year after the Sabbatical Year, when there is not much produce available, and delaying the consumption of the new crop would also cause hardship. When is the court accustomed to intercalate? On the eve of the Sabbatical Year, which causes no particular challenges. Nevertheless, the courts of the house of Rabban Gamliel would intercalate the year in the year after the Sabbatical Year. And they disagree with regard to the issue that is the subject of the dispute between these tanna’im, as it is taught in a baraita: One may not import vegetables in the Sabbatical Year from outside Eretz Yisrael, and our Rabbis permitted importing such produce. According to the opinion that permits importing produce from outside Eretz Yisrael, there is no concern that the food supply will be exhausted. Therefore, the year following the Sabbatical Year may be intercalated. The Gemara asks: What is the reason for the difference between these two opinions concerning importing produce from outside Eretz Yisrael? Rabbi Yirmeya says: The difference between them relates to whether one is concerned for their clods of earth. Although all agree that the earth outside Eretz Yisrael conveys ritual impurity, the tanna’im dispute whether it is therefore forbidden to bring vegetables into Eretz Yisrael due to concern that small clods of earth may cling to them. § The Sages taught in a baraita (Tosefta 2:10): The court may not intercalate the year due to ritual impurity, i.e., in the event that most of the Jewish people are in a state of impurity, to give them enough time to become ritually pure before Passover. Rabbi Yehuda says: The court may intercalate the year due to ritual impurity. Rabbi Yehuda said: There was an incident involving Hezekiah, king of Judea, who intercalated the year due to ritual impurity (II Chronicles 30:2). And after doing so, he requested compassion for himself, as it is written: “For a multitude of the people, even many of Ephraim and Manasseh, Issachar and Zebulun, had not cleansed themselves,

ראש השנה כ״ה א:ז׳-י״ד

תניא אמר להם ר"ג לחכמים כך מקובלני מבית אבי אבא פעמים שבא בארוכה ופעמים שבא בקצרה א"ר יוחנן מ"ט דבי רבי דכתיב (תהלים קד, יט) עשה ירח למועדים שמש ידע מבואו שמש הוא דידע מבואו ירח לא ידע מבואו רבי חייא חזייא לסיהרא דהוה קאי בצפרא דעשרים ותשעה שקל קלא פתק ביה אמר לאורתא בעינן לקדושי בך ואת קיימת הכא זיל איכסי א"ל רבי לר' חייא זיל לעין טב וקדשיה לירחא ושלח לי סימנא דוד מלך ישראל חי וקים ת"ר פעם אחת נתקשרו שמים בעבים ונראית דמות לבנה בעשרים ותשעה לחדש כסבורים העם לומר ר"ח ובקשו ב"ד לקדשו אמר להם ר"ג כך מקובלני מבית אבי אבא אין חדושה של לבנה פחותה מעשרים ותשעה יום ומחצה ושני שלישי שעה וע"ג חלקים ואותו היום מתה אמו של בן זזא והספידה ר"ג הספד גדול לא מפני שראויה לכך אלא כדי שידעו העם שלא קידשו ב"ד את החדש: הלך ר"ע (ומצאו) מיצר כו': איבעיא להו מי מיצר ר"ע מיצר או רבי יהושע מיצר ת"ש דתניא הלך ר"ע ומצאו לרבי יהושע כשהוא מיצר אמר לו [רבי] מפני מה אתה מיצר אמר לו (רבי) עקיבא ראוי לו שיפול למטה י"ב חדש ואל יגזור עליו גזירה זו א"ל רבי תרשיני לומר לפניך דבר אחד שלמדתני אמר לו אמור אמר לו הרי הוא אומר (ויקרא כג, ב) אתם אתם אתם ג' פעמים אתם אפילו שוגגין אתם אפילו מזידין אתם אפילו מוטעין בלשון הזה אמר לו עקיבא נחמתני נחמתני:

Rosh Hashanah 25a:7-14

GEMARA: It is taught in a baraita that Rabban Gamliel said to the Sages, in explanation of his opinion that it is possible for the new moon to be visible so soon after the last sighting of the waning moon: This is the tradition that I received from the house of my father’s father: Sometimes the moon comes by a long path and sometimes it comes by a short one. Rabbi Yoḥanan said: What is the reason for the opinion of the house of Rabbi Yehuda HaNasi, i.e., the house of the heads of the Great Sanhedrin, the source of Rabban Gamliel’s ruling? As it is written: “Who appointed the moon for seasons; the sun knows its going down” (Psalms 104:19). This verse indicates that it is only the sun that knows its going down, i.e., its seasons and the times that it shines are the same every year. In contrast, the moon does not know its going down, as its course is not identical every month. § The Gemara relates that Rabbi Ḥiyya once saw the waning moon standing in the sky on the morning of the twenty-ninth of the month. He took a clump of earth and threw it at the moon, saying: This evening we need to sanctify you, i.e., the new moon must be visible tonight so that we may declare the thirtieth of the month as the New Moon, and you are still standing here? Go and cover yourself for now, so that the new moon will be seen only after nightfall. The Gemara further relates that Rabbi Yehuda HaNasi once said to Rabbi Ḥiyya: Go to a place called Ein Tav and sanctify the New Moon there, and send me a sign that you have sanctified it. The sign is: David, king of Israel, lives and endures. The Sages taught in a baraita: Once the sky was covered with clouds, and the form of the moon was visible on the twenty-ninth of the month. The people thought to say that the day was the New Moon, and the court sought to sanctify it. However, Rabban Gamliel said to them: This is the tradition that I received from the house of my father’s father: The monthly cycle of the renewal of the moon takes no less than twenty-nine and a half days, plus two-thirds of an hour, plus seventy-three of the 1,080 subsections of an hour. The baraita continues: And on that day the mother of the Sage ben Zaza died, and Rabban Gamliel delivered a great eulogy on her behalf. He did this not because she was worthy of this honor; rather, he eulogized her so that the people would know that the court had not sanctified the month, as eulogies are prohibited on the New Moon. § The mishna taught that Rabbi Akiva went and found him distressed that the head of the Great Sanhedrin was forcing him to desecrate the day that he maintained was Yom Kippur. A dilemma was raised before the Sages: Who was distressed? Was Rabbi Akiva distressed or was Rabbi Yehoshua distressed? The Gemara answers: Come and hear, as it is taught in a baraita: Rabbi Akiva went and found Rabbi Yehoshua in a state of distress, and he said to him: My teacher, for what reason are you distressed? Rabbi Yehoshua said to him: Rabbi Akiva, it is fitting for one to fall sick in bed for twelve months, rather than to have this decree issued against him that he should have to desecrate Yom Kippur. Rabbi Akiva said to him: My teacher, allow me to say before you one matter that you yourself once taught me. He said to him: Speak. He said to him: It states with respect to the Festivals: “The appointed seasons of the Lord, which you shall proclaim them [otam] to be sacred convocations (Leviticus 23:2). And it is written: “These are the appointed seasons of the Lord, sacred convocations; you shall proclaim them [otam] in their season” (Leviticus 23:4). And it is written: “These are the appointed seasons of the Lord; you shall proclaim them [otam] to be sacred convocations” (Leviticus 23:37). Three times the verses use the term: Them [otam], which can also be read as you [atem], in plural. This comes to teach: You [atem] are authorized to determine the date of the new month, even if you unwittingly establish the New Moon on the wrong day; you, even if you do so intentionally; you, even if you are misled by false witnesses. In all cases, once the court establishes the day as the New Moon, it is sanctified, and God grants His consent. After hearing this, Rabbi Yehoshua said to him in these words: Akiva, you have consoled me; you have consoled me.

רש"י על ראש השנה כ״ה א:ט׳:ג׳

לאורתא בעינן לקדושיך - צריכין אנו לעשות הלילה יום טוב של ראש השנה לחסר את אלול ולאיים על העדים לומר ראינוהו בזמנו לקדשו למחר ואף על פי שלא ראוהו לפי שהיה עיבור החדש דוחה את יום הכפורים אצל שבת:

Rashi on Rosh Hashanah 25a:9:3

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ראש השנה כ׳ א:ח׳-י״ח

כי אתא עולא אמר עברוה לאלול אמר עולא ידעי חברין בבלאי מאי טיבותא עבדינן בהדייהו מאי טיבותא עולא אמר משום ירקיא רבי אחא בר חנינא אמר משום מתיא מאי בינייהו איכא בינייהו יוה"כ שחל להיות אחר השבת מאן דאמר משום מתיא מעברינן ומאן דאמר משום ירקיא לאימת קא בעי להו לאורתא לאורתא טרח ומייתי ולמ"ד משום ירקיא לעבריה משום מתיא אלא איכא בינייהו יו"ט הסמוך לשבת בין מלפניה בין מלאחריה מ"ד משום ירקיא מעברינן ומאן דאמר משום מתיא אפשר בעממי ולמ"ד משום מתיא לעבריה משום ירקיא אפשר בחמימי אי הכי מאי שנא לדידן אפילו לדידהו נמי לדידן חביל לן עלמא לדידהו לא חביל להו עלמא איני והתני רבה בר שמואל יכול כשם שמעברין את השנה לצורך כך מעברין את החדש לצורך ת"ל (שמות יב, ב) החדש הזה לכם ראש חדשים כזה ראה וקדש אמר רבא לא קשיא כאן לעברו כאן לקדשו והכי קאמר יכול כשם שמעברין את השנה ואת החדש לצורך כך מקדשין את החדש לצורך תלמוד לומר החדש הזה לכם כזה ראה וקדש וכי הא דאמר רבי יהושע בן לוי מאיימין על העדים על החדש שנראה בזמנו לעברו ואין מאיימין על העדים על החדש שלא נראה בזמנו לקדשו איני והא שלח ליה רבי יהודה נשיאה לרבי אמי הוו יודעין שכל ימיו של רבי יוחנן היה מלמדנו מאיימין על העדים על החדש שלא נראה בזמנו לקדשו אע"פ שלא ראוהו יאמרו ראינו אמר אביי לא קשיא הא בניסן ותשרי הא בשאר ירחי

Rosh Hashanah 20a:8-18

§ It is related that when Ulla came from Eretz Yisrael to Babylonia, he said: This year they added an extra day to the month of Elul. Ulla continued and said: Do our Babylonian colleagues understand what benefit we did for them? We pushed off Rosh HaShana for a day, so that the Festival would not occur adjacent to Shabbat. The Gemara asks: What is the benefit in having a weekday between Shabbat and a Festival? Ulla said: Due to the vegetables that would not be picked for two days and those picked beforehand that would no longer be fresh. Rabbi Aḥa bar Ḥanina said: Due to the dead who would not be buried for two days and consequently would begin to decompose. The Gemara asks: What is the practical difference between these two concerns? The Gemara answers: The practical difference between them is in the case where Yom Kippur occurs directly after Shabbat. According to the one who said that the reason is due to the dead that would go unburied for two days, the court adds an extra day to Elul so that Yom Kippur will not occur on Sunday. But according to the one who said that the reason is due to the vegetables that would not be fresh, there is no need to add an extra day to Elul. When would he require the vegetables? Only in the evening following Yom Kippur; and if Yom Kippur falls on Sunday, he can go out in the evening after the fast and bring fresh vegetables. The Gemara asks: But according to the one who says that the reason is due to vegetables, the court should still make Elul full due to the dead, as this is also an important consideration. Rather, the practical difference between them is with regard to the case where the Festival of Rosh HaShana occurs adjacent to Shabbat, either before it or after it. According to the one who said that the reason is due to the vegetables that would wither, the court adds an extra day to Elul. But according to the one who said that the reason is due to the dead that would go unburied, there is no reason to make Elul full, because on a Festival it is possible to arrange that the dead be buried by gentiles. The Gemara asks: But according to the one who said that the reason is due to the dead, the court should still add an extra day to Elul due to the vegetables. The Gemara answers: According to him this is not an important consideration, because it is possible to soak the withered vegetables in hot water and thereby restore their freshness. The Gemara asks: If so, what is different about those who live in Babylonia and those who live in Eretz Yisrael? Why did Ulla specifically say that adding an extra day to Elul was beneficial to us, in Babylonia; it was beneficial to them as well. The Gemara answers: For us in Babylonia the weather is very hot, and so vegetables wither and corpses decompose quickly. But for them in Eretz Yisrael, the weather is not as hot, and vegetables and corpses can be kept for two days. § It was taught above that for various reasons a month can have an extra day added, even if the new moon was seen on the night before the thirtieth. The Gemara challenges this assumption: Is that so? But didn’t Rabba bar Shmuel teach in a baraita: One might have thought that just as the court adds an extra month to a year for some pressing communal need, so too, the court adds an extra day to a month for some similar need. Therefore, the verse states: “This month shall be to you the beginning of months” (Exodus 12:2). This teaches that when there is a moon like this, see it and sanctify the month. When the new moon is seen, the month must be sanctified without delay. Rava said: This is not difficult: Here it is speaking of adding an extra day to the month, although the new moon was seen on the thirtieth, which is permitted; whereas there it is speaking of sanctifying the month on the thirtieth, although the new moon was not yet seen, which is prohibited. And this is what the baraita is saying: One might have thought that just the court adds to a year or a month for some pressing communal need, so too, a month can be sanctified early on the thirtieth even without seeing the new moon. Therefore, the verse states: “This month shall be to you the beginning of months,” which teaches: Only when the moon appears like this, see it and sanctify the month, but not before. The Gemara comments that this is like that which Rabbi Yehoshua ben Levi said: The court may intimidate witnesses through rigorous and confusing examination, so that they will give inadmissible testimony about the new moon that was seen at its due time, the thirtieth of the month. This is so that the court can add an extra day to it, and the New Moon will be sanctified on the thirty-first day. But the court may not intimidate witnesses into giving testimony about the new moon that was not seen on its due time, in order that to sanctify the New Moon early, on the thirtieth. The Gemara asks: Is that so? But didn’t Rabbi Yehuda Nesia, who was the Nasi of the Sanhedrin, send a message to Rabbi Ami: Be aware that all the days of Rabbi Yoḥanan he would teach us that witnesses may be intimidated into giving testimony about the new moon that was not seen in its due time. This was done in order that the new month may be sanctified early, already on the thirtieth. Although the witnesses did not see the moon, they may say: We saw it. Abaye said: This is not difficult: This ruling is referring to Nisan and Tishrei, which may be sanctified early in order to set the Festivals that occur in those months; that ruling is referring to the other months, which may not be sanctified early, even for some other pressing need.

רש"י על ראש השנה כ׳ א:ט׳:א׳-ב׳

משום ירקיא - להפריד שבת ויום טוב זה מזה כדי שלא יכמושו ירקות הנאכלות כשהן חיין בשבת שאחר יו"ט או ביו"ט שאחר שבת: משום מתיא - להפריד שבת ויום הכפורים זה מזה שלא יסריח מת שימות באחד מהן שיהא ראשון ולא יקבר לא היום ולא למחר:

תוספתא סנהדרין ב׳:ב׳

על ג' סימנין מעברין את השנה על האביב ועל פירות האילן ועל התקופה על שנים מעברין ועל אחד אין מעברין ואם עברוה הרי זו מעוברת אם היה <היה> אביב אחד משני סימנין היו שמחין רבן שמעון בן גמליאל אומר אף על התקופה על ג' ארצות מעברין את השנה על יהודה ועל עבר הירדן ועל הגליל על שתים מעברין ועל אחת אין מעברין ואם עברו הרי זו מעוברת ואם היתה ארץ יהודה אחת משתי ארצות היו שמחין מפני אביב שבאה הימנה אין מעברין את השנה לא מפני הגדיים ולא מפני הטלאים לא מפני הגוזלות שלא הגיעו וכולן סעד לשנה ואם עברוה הרי זו מעוברת רבי ינאי אומר משם רשב"ג שהיה אומר בגוזליא רכיכין הן ובאמריא דעדקין ושפר באנפאי ואוסיפית על שתא דא תלתין יומין מעשה ברבן גמליאל וזקנים שהיו עומדין ע"ג מעלות בהר הבית ויוחנן סופר הלך לפניהם ואמרו כתוב לאחנא בני גלילא עילאה ובני גלילא תתאי שלמכון יסגא מהודעין אנחנא לכון דמטא זמן בעורא לאפוקיא מעשריא ממעטניא זיתיא ולאחנא בני דרומא עילאה ובני דרומא תתאה שלמכון יסגא מהודעין אנחנא לכון דימטן זמן לאפוקי מעשריא מעומרי שובילא ולאחנא בני גלותא דבבל ובני גלותא דמדי ושאר כל בני גלותא דישראל שלמכון יסגא מהודעין אנחנא לכון דגוזליא רכיכין ואמריא דעדקין וזימניה דאביבא לא מטא ושפר באנפאי ובאנפי חבראי ואוספנא על שתא דא תלתין יומין.

Tosefta Sanhedrin 2:2

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ספרי דברים קכ״ז:א׳

שמור את חדש האביב. שמור החדש שהוא סמוך לאביב, מפני אביב שיהא בזמנו.

Sifrei Devarim 127:1

(Devarim 16:1) "Observe the month of Aviv": Observe the month close to Aviv, so that aviv (the springtide) fall out in its proper time.

ספרי דברים קכ״ז:ב׳

(סנהדרין יא יג) יכול אם היתה שנה חסרה י"ד יום או ט"ו יום, אתה נותן לו י"ד יום או ט"ו יום? תלמוד לומר "חדש" לא פחות (ולא יותר).

Sifrei Devarim 127:2

I might think that if the year were lacking fourteen or fifteen days, you should add that number of days to it; it is, therefore, written "the month," and not less. ...

ספרי דברים קכ״ז:ג׳

יכול אם היתה חסרה מ"ם יום [או נו"ן יום], אתה נותן להם מ"ם יום או נו"ן יום? תלמוד לומר "חדש", לא פחות ולא יותר.

Sifrei Devarim 127:3

I might think that if it were lacking forty or fifty days, you should add that number of days to it; it is, therefore, written "the month" — not less and not more.

משנה תורה, הלכות קידוש החודש ד׳

(א) שָׁנָּה מְעֻבֶּרֶת הִיא שָׁנָה שֶׁמּוֹסִיפִין בָּהּ חֹדֶשׁ. וְאֵין מוֹסִיפִין לְעוֹלָם אֶלָּא אֲדָר וְעוֹשִׂין אוֹתָהּ שָׁנָה שְׁנֵי אֲדָרִין אֲדָר רִאשׁוֹן וַאֲדָר שֵׁנִי. וּמִפְּנֵי מָה מוֹסִיפִין חֹדֶשׁ זֶה מִפְּנֵי זְמַן הָאָבִיב כְּדֵי שֶׁיְּהֵא הַפֶּסַח בְּאוֹתוֹ זְמַן שֶׁנֶּאֱמַר (דברים טז א) "שָׁמוֹר אֶת חֹדֶשׁ הָאָבִיב" שֶׁיִּהְיֶה חֹדֶשׁ זֶה בִּזְמַן הָאָבִיב. וְלוּלֵא הוֹסָפַת הַחֹדֶשׁ הַזֶּה הַפֶּסַח בָּא פְּעָמִים בִּימוֹת הַחַמָּה וּפְעָמִים בִּימוֹת הַגְּשָׁמִים:

(ב) עַל שְׁלֹשָׁה סִימָנִין מְעַבְּרִין אֶת הַשָּׁנָה. עַל הַתְּקוּפָה וְעַל הָאָבִיב וְעַל פֵּרוֹת הָאִילָן. כֵּיצַד. בֵּית דִּין מְחַשְּׁבִין וְיוֹדְעִין אִם תִּהְיֶה תְּקוּפַת נִיסָן בְּשִׁשָּׁה עָשָׂר בְּנִיסָן אוֹ אַחַר זְמַן זֶה מְעַבְּרִין אוֹתָהּ הַשָּׁנָה. וְיַעֲשׂוּ אוֹתוֹ נִיסָן אֲדָר שֵׁנִי כְּדֵי שֶׁיִּהְיֶה הַפֶּסַח בִּזְמַן הָאָבִיב. וְעַל סִימָן זֶה סוֹמְכִין וּמְעַבְּרִין וְאֵין חוֹשְׁשִׁין לְסִימָן אַחֵר:

(ג) וְכֵן אִם רָאוּ בֵּית דִּין שֶׁעֲדַיִן לֹא הִגִּיעַ הָאָבִיב אֶלָּא עֲדַיִן אָפֵל הוּא. וְלֹא צָמְחוּ פֵּרוֹת הָאִילָן שֶׁדַּרְכָּן לִצְמֹחַ בִּזְמַן הַפֶּסַח. סוֹמְכִין עַל שְׁנֵי סִימָנִין אֵלּוּ וּמְעַבְּרִין אֶת הַשָּׁנָה. וְאַף עַל פִּי שֶׁהַתְּקוּפָה קֹדֶם לְשִׁשָּׁה עָשָׂר בְּנִיסָן הֲרֵי הֵן מְעַבְּרִין. כְּדֵי שֶׁיִּהְיֶה הָאָבִיב מָצוּי לְהַקְרִיב מִמֶּנּוּ עֹמֶר הַתְּנוּפָה בְּשִׁשָּׁה עָשָׂר בְּנִיסָן. וּכְדֵי שֶׁיִּהְיוּ הַפֵּרוֹת צוֹמְחִין כְּדֶרֶךְ כָּל זְמַן הָאָבִיב:

(ד) וְעַל שָׁלֹשׁ אֲרָצוֹת הָיוּ סוֹמְכִין בָּאָבִיב. עַל אֶרֶץ יְהוּדָה וְעַל עֵבֶר הַיַּרְדֵּן וְעַל הַגָּלִיל. וְאִם הִגִּיעַ הָאָבִיב בִּשְׁתֵּי אֲרָצוֹת מֵאֵלּוּ וּבְאַחַת לֹא הִגִּיעַ אֵין מְעַבְּרִין. וְאִם הִגִּיעַ בְּאַחַת מֵהֶן וְלֹא הִגִּיעַ בִּשְׁתַּיִם מְעַבְּרִין אִם עֲדַיִן לֹא צָמְחוּ פֵּרוֹת הָאִילָן. וְאִלּוּ הֵן הַדְּבָרִים שֶׁהֵן הָעִקָּר שֶׁמְּעַבְּרִין בִּשְׁבִילָן כְּדֵי שֶׁיִּהְיוּ הַשָּׁנִים שְׁנֵי חַמָּה:

(ה) וְיֵשׁ שָׁם דְּבָרִים אֲחֵרִים שֶׁהָיוּ בֵּית דִּין מְעַבְּרִין בִּשְׁבִילָן מִפְּנֵי הַצֹּרֶךְ. וְאֵלּוּ הֵן. מִפְּנֵי הַדְּרָכִים שֶׁאֵינָן מְתֻקָּנִין וְאֵין הָעָם יְכוֹלִין לַעֲלוֹת מְעַבְּרִין אֶת הַשָּׁנָה עַד שֶׁיִּפָּסְקוּ הַגְּשָׁמִים וִיתַקְּנוּ הַדְּרָכִים. וּמִפְּנֵי הַגְּשָׁרִים שֶׁנֶּהֶרְסוּ וְנִמְצְאוּ הַנְּהָרוֹת מַפְסִיקִין וּמוֹנְעִין אֶת הָעָם וּמִסְתַּכְּנִין בְּעַצְמָן וּמֵתִים מְעַבְּרִין אֶת הַשָּׁנָה עַד שֶׁיְּתַקְּנוּ הַגְּשָׁרִים. וּמִפְּנֵי תַּנּוּרֵי פְּסָחִים שֶׁאָבְדוּ בַּגְּשָׁמִים וְאֵין לָהֶם מָקוֹם לִצְלוֹת אֶת פִּסְחֵיהֶם מְעַבְּרִין אֶת הַשָּׁנָה עַד שֶׁיִּבָּנוּ הַתַּנּוּרִים וְיִיבְשׁוּ. וּמִפְּנֵי גָּלֻיּוֹת יִשְׂרָאֵל שֶׁנֶּעֶקְרוּ מִמְּקוֹמָן וַעֲדַיִן לֹא הִגִּיעוּ לִירוּשָׁלַיִם מְעַבְּרִין אֶת הַשָּׁנָה כְּדֵי שֶׁיִּהְיֶה לָהֶם פְּנַאי לְהַגִּיעַ:

(ו) אֲבָל אֵין מְעַבְּרִין אֶת הַשָּׁנָה לֹא מִפְּנֵי הַשֶּׁלֶג וְלֹא מִפְּנֵי הַצִּנָּה וְלֹא מִפְּנֵי גָּלֻיּוֹת יִשְׂרָאֵל שֶׁעֲדַיִן לֹא נֶעֶקְרוּ מִמְּקוֹמָם. וְלֹא מִפְּנֵי הַטֻּמְאָה. כְּגוֹן שֶׁהָיוּ רֹב הַקָּהָל אוֹ רֹב הַכֹּהֲנִים טְמֵאִים אֵין מְעַבְּרִין אֶת הַשָּׁנָה כְּדֵי שֶׁיִּהְיֶה לָהֶם פְּנַאי לִטַּהֵר וְיַעֲשׂוּ בְּטָהֳרָה אֶלָּא יַעֲשׂוּ בְּטֻמְאָה. וְאִם עִבְּרוּ אֶת הַשָּׁנָה מִפְּנֵי הַטֻּמְאָה הֲרֵי זוֹ מְעֻבֶּרֶת:

(ז) יֵשׁ דְּבָרִים שֶׁאֵין מְעַבְּרִין בִּשְׁבִילָן כְּלָל אֲבָל עוֹשִׂין אוֹתָן סַעַד לְשָׁנָה שֶׁצְּרִיכָה עִבּוּר מִפְּנֵי הַתְּקוּפָה אוֹ מִפְּנֵי הָאָבִיב וּפֵרוֹת הָאִילָן. וְאֵלּוּ הֵן. מִפְּנֵי הַגְּדָיִים וְהַטְּלָאִים שֶׁעֲדַיִן לֹא נוֹלְדוּ אוֹ שֶׁהֵן מְעַט. ומִפְּנֵי הַגּוֹזָלוֹת שֶׁלֹּא פָּרְחוּ. אֵין מְעַבְּרִין בִּשְׁבִיל אֵלּוּ כְּדֵי שֶׁיִּהְיוּ הַגְּדָיִים וְהַטְּלָאִים מְצוּיִין לִפְסָחִים וְהַגּוֹזָלוֹת מְצוּיִין לִרְאִיָּה אוֹ לְמִי שֶׁנִּתְחַיֵּב בְּקָרְבַּן הָעוֹף. אֲבָל עוֹשִׂין אוֹתָן סַעַד לְשָׁנָה:

(ח) כֵּיצַד עוֹשִׂין אוֹתָן סַעַד לְשָׁנָה. אוֹמְרִין שָׁנָה זוֹ צְרִיכָה עִבּוּר מִפְּנֵי הַתְּקוּפָה שֶׁמָּשְׁכָה אוֹ מִפְּנֵי הָאָבִיב וּפֵרוֹת הָאִילָן שֶׁלֹּא הִגִּיעוּ וְעוֹד שֶׁהַגְּדָיִים קְטַנִּים וְהַגּוֹזָלוֹת רַכִּים:

(ט) אֵין מְעַבְּרִין אֶת הַשָּׁנָה אֶלָּא בִּמְזֻמָּנִין לָהּ. כֵּיצַד. יֹאמַר רֹאשׁ בֵּית דִּין הַגָּדוֹל לִפְלוֹנִי וּפְלוֹנִי מִן הַסַּנְהֶדְרִין הֱיוּ מְזֻמָּנִין לְמָקוֹם פְּלוֹנִי שֶׁנְּחַשֵּׁב וְנִרְאֶה וְנֵדַע אִם שָׁנָה זוֹ צְרִיכָה עִבּוּר אוֹ אֵינָהּ צְרִיכָה. וְאוֹתָן שֶׁהֻזְמְנוּ בִּלְבַד הֵן שֶׁמְּעַבְּרִין אוֹתָהּ. וּבְכַמָּה מְעַבְּרִין אוֹתָהּ. מַתְחִילִין בִּשְׁלֹשָׁה דַּיָּנִין מִכְּלַל סַנְהֶדְרֵי גְּדוֹלָה מִמִּי שֶּׁסָּמְכוּ אוֹתָן. אָמְרוּ שְׁנַיִם לֹא נֵשֵׁב וְלֹא נִרְאֶה אִם צְרִיכָה עִבּוּר אִם לָאו וְאֶחָד אָמַר נֵשֵׁב וְנִבְדֹּק. בָּטֵל יָחִיד בְּמִעוּטוֹ. אָמְרוּ שְׁנַיִם נֵשֵׁב וְנִרְאֶה וְאֶחָד אוֹמֵר לֹא נֵשֵׁב. מוֹסִיפִין עוֹד שְׁנַיִם מִן הַמְזֻמָּנִים וְנוֹשְׂאִים וְנוֹתְנִין בַּדָּבָר:

(י) שְׁנַיִם אוֹמְרִים צְרִיכָה עִבּוּר וּשְׁלֹשָׁה אוֹמְרִין אֵינָהּ צְרִיכָה. בָּטְלוּ שְׁנַיִם בְּמִעוּטָן. שְׁלֹשָׁה אוֹמְרִין צְרִיכָה עִבּוּר וּשְׁנַיִם אוֹמְרִין אֵינָהּ צְרִיכָה עִבּוּר. מוֹסִיפִין שְׁנַיִם מִן הַמְזֻמָּנִין לָהּ וְנוֹשְׂאִין וְנוֹתְנִין וְגוֹמְרִין בְּשִׁבְעָה. אִם גָּמְרוּ כֻּלָּם לְעַבֵּר אוֹ שֶׁלֹּא לְעַבֵּר עוֹשִׂין כְּמוֹ שֶׁגָּמְרוּ. וְאִם נֶחְלְקוּ הוֹלְכִים אַחַר הָרֹב בֵּין לְעַבֵּר בֵּין שֶׁלֹּא לְעַבֵּר. וְצָרִיךְ שֶׁיְּהֵא רֹאשׁ בֵּית דִּין הַגָּדוֹל שֶׁהוּא רֹאשׁ יְשִׁיבָה שֶׁל אֶחָד וְשִׁבְעִים מִכְּלַל הַשִּׁבְעָה. וְאִם גָּמְרוּ בִּשְׁלֹשָׁה לְעַבֵּר הֲרֵי זוֹ מְעֻבֶּרֶת וְהוּא שֶׁיְּהֵא הַנָּשִׂיא עִמָּהֶן אוֹ שֶׁיִּרְצֶה. וּבְעִבּוּר הַשָּׁנָה מַתְחִילִין מִן הַצַּד. וּלְקִדּוּשׁ הַחֹדֶשׁ מַתְחִילִין מִן הַגָּדוֹל:

(יא) אֵין מוֹשִׁיבִין לְעִבּוּר הַשָּׁנָה לֹא מֶלֶךְ וְלֹא כֹּהֵן גָּדוֹל. מֶלֶךְ מִפְּנֵי חֵילוֹתָיו וּמִלְחֲמוֹתָיו שֶׁמָּא דַּעְתּוֹ נוֹטָה בִּשְׁבִילָן לְעַבֵּר אוֹ שֶׁלֹּא לְעַבֵּר. וְכֹהֵן גָּדוֹל מִפְּנֵי הַצִּנָּה שֶׁמָּא לֹא תִּהְיֶה דַּעְתּוֹ נוֹטָה לְעַבֵּר כְּדֵי שֶׁלֹּא יָבֹא תִּשְׁרֵי בִּימֵי הַקֹּר וְהוּא טוֹבֵל בְּיוֹם הַכִּפּוּרִים חָמֵשׁ טְבִילוֹת:

(יב) הָיָה רֹאשׁ בֵּית דִּין הַגָּדוֹל וְהוּא הַנִּקְרָא נָשִׂיא בְּדֶרֶךְ רְחוֹקָה אֵין מְעַבְּרִין אוֹתָהּ אֶלָּא עַל תְּנַאי אִם יִרְצֶה הַנָּשִׂיא. בָּא וְרָצָה הֲרֵי זוֹ מְעֻבֶּרֶת. לֹא רָצָה אֵינָהּ מְעֻבֶּרֶת. וְאֵין מְעַבְּרִין אֶת הַשָּׁנָה אֶלָּא בְּאֶרֶץ יְהוּדָה שֶׁהַשְּׁכִינָה בְּתוֹכָהּ שֶׁנֶּאֱמַר (דברים יב ה) "לְשִׁכְנוֹ תִדְרְשׁוּ". וְאִם עִבְּרוּהָ בַּגָּלִיל מְעֻבֶּרֶת. וְאֵין מְעַבְּרִין אֶלָּא בַּיּוֹם. וְאִם עִבְּרוּהָ בַּלַּיְלָה אֵינָהּ מְעֻבֶּרֶת:

(יג) יֵשׁ לְבֵית דִּין לְחַשֵּׁב וְלִקְבֹּעַ וְלֵידַע אֵי זוֹ שָׁנָה תִּהְיֶה מְעֻבֶּרֶת בְּכָל עֵת שֶׁיִּרְצֶה אֲפִלּוּ לְכַמָּה שָׁנִים. אֲבָל אֵין אוֹמְרִין שָׁנָה פְּלוֹנִית מְעֻבֶּרֶת אֶלָּא אַחַר רֹאשׁ הַשָּׁנָה הוּא שֶׁאוֹמֵר שָׁנָה זוֹ מְעֻבֶּרֶת. וְדָבָר זֶה מִפְּנֵי הַדְּחָק אֲבָל שֶׁלֹּא בִּשְׁעַת הַדְּחָק אֵין מוֹדִיעִין שֶׁהִיא מְעֻבֶּרֶת אֶלָּא בַּאֲדָר הוּא שֶׁאוֹמֵר שָׁנָה זוֹ מְעֻבֶּרֶת וְחֹדֶשׁ הַבָּא אֵינוֹ נִיסָן אֶלָּא אֲדָר שֵׁנִי. אָמְרוּ לִפְנֵי רֹאשׁ הַשָּׁנָה שָׁנָה זוֹ שֶׁתִּכָּנֵס מְעֻבֶּרֶת אֵינָהּ מְעֻבֶּרֶת בַּאֲמִירָה זוֹ:

(יד) הִגִּיעַ יוֹם שְׁלֹשִׁים בַּאֲדָר וְלֹא עִבְּרוּ עֲדַיִן הַשָּׁנָה לֹא יְעַבְּרוּ אוֹתָהּ כְּלָל. שֶׁאוֹתוֹ הַיּוֹם רָאוּי לִהְיוֹת רֹאשׁ חֹדֶשׁ נִיסָן וּמִשֶּׁיִּכָּנֵס נִיסָן וְלֹא עִבְּרוּ אֵינָן יְכוֹלִים לְעַבֵּר. וְאִם עִבְּרוּהָ בְּיוֹם שְׁלֹשִׁים שֶׁל אֲדָר הֲרֵי זוֹ מְעֻבֶּרֶת. בָּאוּ עֵדִים אַחַר שֶׁעִבְּרוּ וְהֵעִידוּ עַל הַיָּרֵחַ הֲרֵי אֵלּוּ מְקַדְּשִׁין אֶת הַחֹדֶשׁ בְּיוֹם שְׁלֹשִׁים וְיִהְיֶה רֹאשׁ חֹדֶשׁ אֲדָר שֵׁנִי. וְאִלּוּ קִדְּשׁוּהוּ קֹדֶם שֶׁיְּעַבְּרוּ אֶת הַשָּׁנָה שׁוּב לֹא הָיוּ מְעַבְּרִין שֶׁאֵין מְעַבְּרִין בְּנִיסָן:

(טו) אֵין מְעַבְּרִין אֶת הַשָּׁנָה בִּשְׁנַת רְעָבוֹן שֶׁהַכּל רָצִים לְבַיִת הַגְּרָנוֹת לֶאֱכל וְלִחְיוֹת וְאִי אֶפְשָׁר לְהוֹסִיף לָהֶן זְמַן לֶאֱסֹר הֶחָדָשׁ. וְאֵין מְעַבְּרִין בִּשְׁבִיעִית שֶׁיַּד הַכּל שׁוֹלֶטֶת עַל הַסְּפִיחִין וְלֹא יִמְצְאוּ לְקַּרֵב הָעֹמֶר וּשְׁתֵּי הַלֶּחֶם. וּרְגִילִין הָיוּ לְעַבֵּר בְּעֶרֶב שְׁבִיעִית:

(טז) יֵרָאֶה לִי שֶׁזֶּה שֶׁאָמְרוּ חֲכָמִים אֵין מְעַבְּרִין בִּשְׁנַת רְעָבוֹן וּבִשְׁבִיעִית. שֶׁלֹּא יְעַבְּרוּ בָּהֶם מִפְּנֵי צֹרֶךְ הַדְּרָכִים וְהַגְּשָׁרִים וְכַיּוֹצֵא בָּהֶם. אֲבָל אִם הָיְתָה הַשָּׁנָה רְאוּיָה לְהִתְעַבֵּר מִפְּנֵי הַתְּקוּפָה אוֹ מִפְּנֵי הָאָבִיב וּפֵרוֹת הָאִילָן מְעַבְּרִין לְעוֹלָם בְּכָל זְמַן:

(יז) כְּשֶׁמְּעַבְּרִין בֵּית דִּין אֶת הַשָּׁנָה כּוֹתְבִין אִגְּרוֹת לְכָל הַמְּקוֹמוֹת הָרְחוֹקִים וּמוֹדִיעִים אוֹתָן שֶׁעִבְּרוּהָ וּמִפְּנֵי מָה עִבְּרוּ. וְעַל לְשׁוֹן הַנָּשִׂיא נִכְתָּבוֹת. וְאוֹמֵר לָהֶן יוֹדֵעַ לָכֶם שֶׁהִסְכַּמְתִּי אֲנִי וַחֲבֵרַי וְהוֹסַפְנוּ עַל שָׁנָה זוֹ כָּךְ וְכָךְ. רָצוּ תִּשְׁעָה וְעֶשְׂרִים יוֹם רָצוּ שְׁלֹשִׁים יוֹם. שֶׁחֹדֶשׁ הָעִבּוּר הָרְשׁוּת לְבֵית דִּין לְהוֹסִיפוֹ מָלֵא אוֹ חָסֵר לָאֲנָשִׁים הָרְחוֹקִים שֶׁמּוֹדִיעִין אוֹתָם. אֲבָל הֵם לְפִי הָרְאִיָּה הֵם עוֹשִׂים אִם מָלֵא אִם חָסֵר:

Mishneh Torah, Sanctification of the New Month 4

(1) A leap year is a year to which an extra month is added. Only Adar is the month that is ever added, so that a leap year has two months of Adar: a first Adar and a second Adar. Why is just this month added? Because of the spring season, so that Pesaḥ should be observed during the barley season, as it is written: "Observe the month of Aviv, and keep the Passover…" (Deuteronomy 16:1), implying that this month of Nisan should occur during the spring. Without the addition of this month of Adar, Passover would occur sometimes in the summer and sometimes in the rainy season [of winter].

(2) For three indicators do we make the year a leap year. For the season, for the Spring [state of the barley] and for the fruit of the trees. How is that? The court calculates and determines – if the season of Nissan (when the sun enters Aries) will be on the sixteenth of Nissan or after that time, they make that year into a leap year. And they make that Nissan [into] Second Adar, so that Passover will be during the time of Spring. And we may rely on this indicator and make leap years, and [then] not be concerned about another indicator.

(3) And likewise if the court saw that the Spring [state of the barley] has yet to arrive, but it is rather still late; and the fruit of the trees that tend to sprout around Passover have not sprouted – we rely on these two indicators and make the year a leap year. And even though the season [arrived] before the sixteenth of Nissan – they surely make it a leap year, so that the Spring [barley] will be present to offer up the waved omer from it on the sixteenth of Nissan; and so that the fruit will sprout like is the way of every Spring [season].

(4) And we rely on three lands with respect to the Spring [state of the barley]: On the Land of Yehudah, on Transjordan and on the Galilee. And if the Spring arrived in two of these [lands], but not in one – we do not make a leap year. However, if it arrived in one of them, but it did not arrive in two – we make a leap year, if the fruit of the trees has yet to sprout. And these are the main things for which we make leap years, in order that the years will be solar years.

(5) And there exist other things for which the court makes leap years due to necessity. And these are them: Because of the roads that are not mended and the people are unable to go up [to Jerusalem], we make the year a leap year until the rain stops and the roads are mended. And because of the bridges which were destroyed and the rivers are found blocking and preventing the people and [so the people] are endangering themselves and dying, we make the year a leap year until they mend the bridges. And because of the ovens [for the] Pesach sacrifice that were destroyed in the rain and [the people] do not have a place to roast their Pesach sacrifices, we make the year a leap year until they will have built the ovens and [the ovens] will have dried. And because of the Israelite exiles that have left from their place and have not yet arrived in Jerusalem, we make the year a leap year in order that they will have enough time to arrive.

(6) But we don't make the year a leap [year] – not for the snow, not for the cold and not for the Israelite exiles that have not yet left from their place. And not for impurity: For example, were the majority of the congregation or the majority of the priests impure, we don't make the year a leap year in order that they will have avaialable time to purify themselves and do [the offerings] in purity. Rather they do [them] in impurity. And if they made the year a leap year because of impurity, it is surely a leap year.

(7) There are things for which we don't make a leap year at all; but we do make them a support for a year that needs to become a leap [year] because of the season or because of the Spring [state of the barley] and the fruits of the trees. And these are them: Because of the goats and sheep that are yet to be born or which are few. And because of the chicks that have not [yet grown enough to have] flown. We do not make a leap year because of these – in order that the goats and sheep should be accessible for the Pesach sacrifices; and [that] the chicks be accessible for the offering of being seen (reiah) or for those who are obligated in a sacrifice of fowl. But we do make them a support for the year.

(8) How do we make them a support for the year? We say, "This year needs intercalation because of the season that has dragged"; or "because of the Spring and the fruit of the trees that are yet to arrive" – "and further since the goats are small and the chicks are delicate."

(9) A year should be intercalated only by those who were invited to participate in the act of intercalation. How is this done? The chief justice of the Supreme Court should say to certain members of the Sanhedrin: "You are invited to come to such and such a place, that we may together calculate and find out whether this year should be intercalated or not." Only those invited may decide about the intercalation of the year. And with how many [judges] do we make it a leap year? We start with three judges from the great Sanhedrin, from those that were ordained. [If] two said "We should not sit and not see whether making a leap [year] is necessary or if not," and one says, "We should sit and check" – the individual is nullified from his [being a] minority. [If] two said "We should sit and check," and one says, "We should not sit" – we add two more from those invited and debate the matter back and forth.

(10) If two of the five members of the council say that the year should be intercalated, and three say that it should not, the minority of two does not count. If three say that it should be intercalated, and two say that it should not, two members are added to the council from among those who have been invited, and they discuss the matter and decide with a panel of seven. If all seven of them unanimously decide to intercalate or not to intercalate, their decision is adhered to; but if they disagree, the opinion of the majority is followed. And there is a need to have head of the High Court – who is the head of the yeshiva of seventy-one – among the seven. And if they concluded with three to make a leap year, it is a leap year so long as the [head of the court] is with them or agrees. And with regards to making the year a leap year, we start [the discussion] from the side (from the lesser judges). But to sanctify the month, we start with the greatest.

(11) A king or a high priest must not be placed as a member of the council on the intercalation of the year. A king is not eligible on account of his armies and far-flung campaigns, lest he may be inclined to intercalate or not to intercalate in their interests. A high priest is not eligible because he may be concerned about the cold weather; he may not be inclined to intercalate, so that the month of Tishri should not occur in the cold season, when he must take five baths of purification on Yom Kippur.

(12) If the chief justice of the Supreme Court, who bears the title of Nasi, happens to be away on a distant trip, the year can be intercalated only on condition that the Nasi will consent. If he arrived and gave his consent, the intercalation remains valid; if he did not consent, the intercalation is invalid. And we only make the year a leap year in the Land of Yehudah. For the Divine Presence is there, as it stated (Deuteronomy 12:5), "to dwell It there; you shall seek." But if they made it a leap year in the Galilee, it is a leap year. And we only make it a leap year during the day. But if they made it a leap year at night, it is not a leap year.

(13) The court is able to calculate, set and determine which year will be a leap year at any time they want, even for several years. But they may not say, "Year x is a leap year." Rather it is after Rosh Hashanah that they may say, "This year is a leap year." And this matter is [only] because of a pressing situation. But at a time when there is no pressing situation, we may not make [it] known that it is a leap year [right after Rosh Hashanah]. Rather it is in Adar that they may say "This year is a leap year; and the coming month is not Nissan but rather Second Adar." [If] they said before Rosh Hashanah, "This year that is beginning is a leap year," it is not [turned into] a leap year with this statement.

(14) [If] the thirtieth day of Adar arrived and they were yet to make the year a leap year, they may not make it a leap year at all. For that day is fitting to be the first of the month of Nissan; and once Nissan has entered and they have not made it a leap year, they are not able to make a leap year. And if they made it a leap year on the thirtieth day of Adar, it is surely a leap year. [If] witnesses came after they made it a leap year and testified about the moon, they sanctify the month on the thirtieth day and it will be the first of the month of Second Adar. But if they sanctified it before they made the year a leap year, they could no longer have made [it] a leap year. For we do not make leap years in Nissan.

(15) We may not make the year a leap year in a year of famine. For everyone runs to the threshing floors to eat and to live; so it is impossible to add time to them, to forbid the new [grain] (which will only become permissible on the sixteenth of Nissan). And we may [also] not make a leap year on a sabbatical year. For everyone's hand is controlling the undergrowth; so they will not find [grain] for the omer offering and the two breads. And they were used to making a leap year on the eve of a sabbatical year.

(16) It seems to me that that which the Sages said, "We may not make a leap year in a year of famine and on the sabbatical year," is that we may not make a leap [year] because of the necessity of the roads and the bridges and that which is similar to them. But if the year was fitting to be made a leap year because of the season or because of the Spring [status of the barley] and the fruit of the trees, we always make a leap year at any time.

(17) When the court makes the year a leap year, they write letters to all the distant places and inform them that it has been made a leap year, and for what reason it was made a leap year. And they are written in the wording of the [head of the court]: And he says to them, "Let it be known to you that I and my colleagues have agreed and we have added to this year such and such [days]" – [if] they want, twenty-nine days, [if] they want, thirty days. For [regarding] the leap year month, the court has the authority to add a full [month] or a lacking [month] for the people far away whom they are informing. But they themselves (in the Land of Israel) go according to the sighting – whether it is full or it is lacking.