(א) אַרְבָּעָה רָאשֵׁי שָׁנִים הֵם. בְּאֶחָד בְּנִיסָן רֹאשׁ הַשָּׁנָה לַמְּלָכִים וְלָרְגָלִים. בְּאֶחָד בֶּאֱלוּל רֹאשׁ הַשָּׁנָה לְמַעְשַׂר בְּהֵמָה. רַבִּי אֶלְעָזָר וְרַבִּי שִׁמְעוֹן אוֹמְרִים, בְּאֶחָד בְּתִשְׁרֵי. בְּאֶחָד בְּתִשְׁרֵי רֹאשׁ הַשָּׁנָה לַשָּׁנִים וְלַשְּׁמִטִּין וְלַיּוֹבְלוֹת, לַנְּטִיעָה וְלַיְרָקוֹת. בְּאֶחָד בִּשְׁבָט, רֹאשׁ הַשָּׁנָה לָאִילָן, כְּדִבְרֵי בֵית שַׁמַּאי. בֵּית הִלֵּל אוֹמְרִים, בַּחֲמִשָּׁה עָשָׂר בּוֹ:
(1) They are four days in the year that serve as the New Year, each for a different purpose: On the first of Nisan is the New Year for kings; it is from this date that the years of a king’s rule are counted. And the first of Nisan is also the New Year for the order of the Festivals, as it determines which is considered the first Festival of the year and which the last. On the first of Elul is the New Year for animal tithes; all the animals born prior to that date belong to the previous tithe year and are tithed as a single unit, whereas those born after that date belong to the next tithe year. Rabbi Elazar and Rabbi Shimon say: The New Year for animal tithes is on the first of Tishrei. On the first of Tishrei is the New Year for counting years, as will be explained in the Gemara; for calculating Sabbatical Years and Jubilee Years, i.e., from the first of Tishrei there is a biblical prohibition to work the land during these years; for planting, for determining the years of orla, the three-year period from when a tree has been planted during which time its fruit is forbidden; and for tithing vegetables, as vegetables picked prior to that date cannot be tithed together with vegetables picked after that date. On the first of Shevat is the New Year for the tree; the fruit of a tree that was formed prior to that date belong to the previous tithe year and cannot be tithed together with fruit that was formed after that date; this ruling is in accordance with the statement of Beit Shammai. But Beit Hillel say: The New Year for trees is on the fifteenth of Shevat.
- Why this time of year?
-Tosfot Yom Tov
(ב) יש להתבונן בענין יום ט"ו שבט שאין אומרים בו תחנון הלוא מה שהוא ר"ה לאילן הוא דבר טבעי שיצאו רוב גשמי השנה ועלה השרף באילנות ונמצאו הפירות חונטין מעתה, ומה ענין שלא יאמר בו תחנון אחר שאין בו קדושה ולא מצוה ולא נעשה בו נס ולא ענין מעניני ישראל, וחמשה עשר באב אמרו ז"ל בש"ס שלהי תענית איזה טעמים שהי' בו ענינים נוגעים לישראל, אבל ט"ו בשבט מה רבותא דידי', ונראה דהנה כתיב כי כאשר ירד הגשם והשלג מן השמים ושמה לא ישוב כי אם הרוה את הארץ והולידה והצמיחה וגו' כן יהי' דברי אשר יצא מפי וגו', הנה המשיל הנביא דבר ה' לגשמים המצמיחים, ונראה דענין האילן הוא המחבר את הפרי לארץ, והוא ממוצע בין הארץ להפרי, ויש בו כח המחבר, ונראה שרמז יש בגימטריא שלו אילן גימטריא צ"א כמספר שני השמות הוי' ואד', אשר שמים וארץ מתיחסים אליהם, והוא חיבור שמים וארץ, ומן מהותו שבגשמיות נלמוד על רוחניותו וע"כ נמשל בו האדם כדכתיב כי האדם עץ השדה, כי צורת האדם הוא לחבר העליונים ותחתונים, באשר יש בו נשמה מהעליונים וגוף נושא הנשמה מהתחתונים, ואמרו ז"ל בטעם עגלה ערופה מפני שלא הניח לו לעשות פירות מאי פירות מצות, כי מצות הם בהתדמות פרי הגדל באילן שיש בהפרי כח רוחני המזין ומחי' את האדם, כידוע פירוש האריז"ל בפסוק כי לא על הלחם לבדו יחי' האדם כי על כל מוצא פי ה' יחי' האדם, היינו מוצא פי ה' שיש בהלחם, וגוף הפרי הוא נושא להרוחניות שבו, כן המצות הם רמ"ח אברים דמלכא וגוף המצוה היא נושא להרוחנית שבמצוה, ואדם העושה את המצוה באשר יש בו כח המחבר עליונים ותחתונים, ע"כ נמצא כח במעשה מצות שהוא עושה חיבור וצירוף עליונים ותחתונים, מעשה המצוה מהתחתונים ורוחנית שבו מהעליונים, דומה לאילן שיש בו כח המחבר ומוציא פרי שיש בו חיבור כנ"ל, ואף שנמצא פרי הארץ שיש בהם רוחנית ומצא פי ה', ומ"מ אינו נעשה ע"י אמצעי, וכמו שנמצא גם במקומות הארץ מקום המקדש שהי' מעולם המחבר עליונים ותחתונים כבמדרש אף בלי אמצעות האדם אלא שהקדושה שבמצות היא באמצעות האדם:
(2) We should contemplate about the idea of TuBiShevat, why we do not say the supplicational prayers (Tachanun). Is not its being the new year of trees something natural? That most of the year’s rains have fallen, such that the sap has risen in the trees; and from then on, the fruits emerge! If so, what is the idea of not saying the supplicational prayers on it? For it has no holiness and no commandment; no miracle happened on it, nor anything [else] that relates to the Jewish people. About the 15th of Av, [the Sages,] may their memory be blessed, spoke at the end of Taanit in the Talmud about some of the reasons [for it], that there were things that occurred on it that related to the Jewish people. But what is the novelty of Tu BiShevat? And it appears [to me as follows]: That behold it is written (Isaiah 55:10-11), "For as the rain or snow drops from heaven and returns not there, but soaks the earth and makes it bring forth vegetation, etc. So is the word that issues from My mouth, etc." Behold the prophet compared the word of God to the rains that bring things forth [produce]. So it appears that the idea of a tree is something that connects the fruit to the ground; and it is what is in the middle between the fruit and the ground and has the power of connection. And it appears that it carries a hint in its numerical equivalent (gematria). Ilan (tree) is 91, the numerical equivalent of the names of the Existence and Lordship of God, to which the Heavens and Earth relate. So it is the connection of the Heavens and the Earth. And we can learn from the essence of the physical about the spiritual; and this is why man is compared to [a tree], as it is written (Deuteronomy 20:19), "for are the trees of the field human beings." For the form of man is to connect the upper realm and the lower realm, in that he has a soul from the upper realm and a body, which bears the soul, from the lower realm. And [the Sages,] may their memory be blessed, said about the reason for the beheaded calf (being killed in its prime, is that it is symbolic), that he (the man murdered) was not allowed to make fruits. What are fruits [here? The fulfillment of] commandments. For the commandments are comparable to the fruit that grows on trees. As in the fruit, it has the spiritual power to sustain and give life to man. This is as per the explanation of the Ari, may his memory be blessed, to the verse (Deuteronomy 8:3), "not by bread alone does man live, but rather by all that issues from the mouth of the Lord does man live" - meaning by that which issues from the mouth of the Lord that is in the bread. And the body of the fruit is what bears the spirituality that is in it. So too are commandments the 248 limbs of the King. and the body of the commandments are what bears the spirituality in the commandment. And when a person does a commandment - since he has the power to connect the higher realm and the lower realm, it therefore comes out that there is the power in the act of the commandment that he does to connect and attach the higher realm and the lower realm, the act of the commandment from the lower realm and the spirituality in it from the higher realm. This is comparable to a tree that has the power to connect, and issues fruit that connects, as mentioned above. And this is so even though there are fruits of the ground (that grow straight from the ground and not from trees) and they have spirituality and that which issues from the mouth of the Lord in them, and it is nevertheless not made by way of an intermediary. And that is like there is also, among places in the world, the place of the Temple, that was always a connection for the upper realm and the lower realm, as per the Midrash, even without man as an intermediary. However the holiness in the commandments is [always] with man as an intermediary.
Shmuel Bornzshstein (1910-1926)
(22) Then Moses caused Israel to set out from the Sea of Reeds. They went on into the wilderness of Shur; they traveled three days in the wilderness and found no water. (23) They came to Marah, but they could not drink the water of Marah because it was bitter; that is why it was named Marah.*Marah I.e., “bitter.” (24) And the people grumbled against Moses, saying, “What shall we drink?” (25) So he cried out to ה', and ה' showed him a piece of wood; he threw it into the water and the water became sweet. There [God] made for them a fixed rule; there they were put to the test. (26) [God] said, “If you will heed your God ה' diligently, doing what is upright in God’s sight, giving ear to God’s commandments and keeping all God’s laws, then I will not bring upon you any of the diseases that I brought upon the Egyptians, for I ה' am your healer.” (27) And they came to Elim, where there were twelve springs of water and seventy palm trees; and they encamped there beside the water.
Some commentators say that he taught them details about the vegetation they would encounter in the desert, which plants had therapeutic value, which were poisonous, etc., etc. The word חק applied to phenomena which were known only empirically, whereas the word משפט applies to knowledge of the inner workings and the why and wherefore of the phenomena in question.
-Rabbenu Bahya
On the other hand, Rabbi Simeon bar Yohai explains the phrase “Vayorehu Hashem etz” as “God taught Moses Torah.” According to this interpretation, the “etz” in the verse refers to “etz hayim hee,“ meaning “it (the Torah) is a tree of life.” In a similar vein, the Toras Menachem brings a beautiful literal reading from the Zohar suggesting that it was a piece of wood from the Etz Hayim–the original Tree of Life in the Garden of Eden.
https://www.myjewishlearning.com/article/where-the-wood-meets-water/
Targum Jerusalem, Exodus 15:25
And Mosheh prayed before the Lord, and the Word of the Lord showed him the tree of Ardiphne, and he cast it into the midst of the waters, and the waters were made sweet. There did the Word of the Lord show unto him statutes and orders of judgment, and there He tried him with trials in the tenth trial.
Duties of the Heart, Fourth Treatise on Trust 4:39
It is even possible that He will heal him through something that is normally very harmful, as you know from the story of Elisha and the bad water, that he healed their damaging properties with salt (Melachim II 2:19), and similarly "And G-d showed him a tree and he tossed it into the waters [and the waters became sweet]" (Shmos 15:25), And the midrash tanchuma there explains that this was a bitter, oleander tree. Another example, "let him smear crushed figs on the boils, and he will heal" (Yeshaya 38:21) (and figs normally damage even healthy flesh - PL). And you already know of what happened to the pious king Asa when he trusted in the doctors, and removed his trust in G-d regarding his illness, the sharp rebuke he received for this (i.e. because he did not pray to be healed). And the verse says: "For He brings pain and binds it; He wounds, and His hands heal." (Iyov 5:18).
-Bahya ibn Paukdah
and both the Targums of Jonathan and Jerusalem call it the bitter tree, Ardiphne, which Cohen de Lara F13 makes to be the same which botanists call Rhododaphne or rose laurel, and which, he says, bears flowers like lilies, which are exceeding bitter, and are poison to cattle; and so says Baal Aruch F14; and much the same has Elias Levita F15:
https://www.biblestudytools.com/commentaries/gills-exposition-of-the-bible/exodus-15-25.html#google_vignette
The Five Books of Moses, by Everett Fox, Exodus, Part II; In the Wilderness, Grumbling I 2-4
The first of the wilderness narratives is linked to what has gone before via the theme of water. Fresh from their rescue from death at the sea, the Israelites look for water in the desert and find the discovery of unpotable water intolerable. The key word, especially for the many later wilderness traditions such as we find in Numbers, is “grumbled” (Heb. lyn), which leads to God’s nurturing of the people. Strangely, the theme of undrinkable water recalls the beginning of the plague sequence in Egypt (7:20–21).
Right away in this first desert episode we are told the purpose of Israel’s journey: God is testing them, to see if they will “hearken” to what he bids them to do. The language is in the style of Deuteronomy. One should also mention the idea of “law and judgment,” indicating another crucial desert theme: Israel’s ability or inability to govern itself.
-Everett Fox