דכתיב (דברים כב, יא) לא תלבש שעטנז גדילים תעשה לך
As it is written: “You shall not wear diverse kinds of wool and linen together. You shall make for yourself twisted fringes on the four corners of your covering with which you cover yourself” (Deuteronomy 22:11–12). These verses teach that despite the prohibition against wearing diverse kinds of wool and linen, it is permitted to prepare ritual fringes of diverse kinds, e.g., sky-blue dyed threads of wool on linen garments. This shows that the positive mitzva of ritual fringes overrides the prohibition of diverse kinds.
ואמר רבי אלעזר סמוכים מן התורה מנין שנאמר (תהלים קיא, ח) סמוכים לעד לעולם עשוים באמת וישר
And Rabbi Elazar said: From where in the Torah is it derived that one may draw homiletical interpretations from the juxtaposition of verses? In other words, from where is it derived that the fact that certain verses are adjacent one to the other is a reason to apply the halakhot from one verse to the other? As it is stated: “The works of His hands in truth and justice, all His commandments are sure. Juxtaposed forever and ever, made in truth and uprightness” (Psalms 111:7–8). This verse indicates that it is appropriate to draw inferences from the juxtaposition of God’s commandments.
ואמר רב ששת אמר ר' אלעזר משום רבי אלעזר בן עזריה מנין ליבמה שנפלה לפני מוכה שחין שאין חוסמין אותה שנאמר (דברים כה, ד) לא תחסום שור בדישו וסמיך ליה כי ישבו אחים יחדיו
And similarly, Rav Sheshet said that Rabbi Elazar said in the name of Rabbi Elazar ben Azarya: From where is it derived with regard to a yevama who came before a yavam afflicted with boils that one may not muzzle her, i.e., she cannot be forced to enter into levirate marriage, and he is compelled to release her by ḥalitza? As it is stated: “You shall not muzzle an ox while it treads out the corn” (Deuteronomy 25:4), and, juxtaposed to it, is the verse: “If brothers dwell together” (Deuteronomy 25:5), which begins the passage that deals with the halakhot of levirate marriage. This teaches that just as it is prohibited to muzzle the ox, so too, one may not muzzle and ignore the complaints of a yevama who does not wish to marry a yavam afflicted with boils.
ואמר רב יוסף אפילו למאן דלא דריש סמוכים בעלמא במשנה תורה דריש דהא ר' יהודה בעלמא לא דריש ובמשנה תורה דריש
And Rav Yosef said: Even according to the one who does not generally derive homiletic interpretations from juxtaposed verses, nevertheless, he does derive them from Deuteronomy, as Rabbi Yehuda does not generally derive homiletic interpretations from juxtaposed verses, and yet he does derive them from Deuteronomy.
ובעלמא מנלן דלא דריש דתניא בן עזאי אומר נאמר (שמות כב, יז) מכשפה לא תחיה ונאמר כל שוכב עם בהמה מות יומת סמכו ענין לו מה שוכב עם בהמה בסקילה אף מכשפה בסקילה
§ The Gemara asks: And from where do we derive that Rabbi Yehuda generally does not derive homiletic interpretations from juxtaposed verses? As it is taught in a baraita with regard to the punishment of a sorceress that ben Azzai says that it is stated: “You shall not allow a sorceress to live” (Exodus 22:17), although the manner of her execution is not specified, and it is stated: “Whoever lies with a beast shall surely be put to death” (Exodus 22:18). The Torah juxtaposed this matter to that so as to say: Just as one who lies with a beast is executed by stoning (see Leviticus 20:16), so too, a sorceress is executed by stoning.
א"ל ר' יהודה וכי מפני שסמכו ענין לו נוציא זה לסקילה
With regard to this proof, Rabbi Yehuda said to ben Azzai: And simply due to the fact that the Torah juxtaposed this matter to that one, shall we take this person out to be stoned? Should he be sentenced to the most severe of the death penalties on the basis of a juxtaposition of passages?
אלא אוב וידעוני בכלל מכשפים היו ולמה יצאו להקיש להם ולומר לך מה אוב וידעוני בסקילה אף מכשפה בסקילה
Rather, Rabbi Yehuda claims that the source is the following statement: Mediums and wizards were included among all sorcerers. And why were they singled out from the rest in the verse: “And a man or a woman who is a medium or a wizard shall surely be put to death; they shall stone them with stones, their blood is upon them” (Leviticus 20:27)? It is to draw an analogy to them and say to you: Just as a medium and a wizard are executed by stoning, so too, a sorceress is executed by stoning. This shows that Rabbi Yehuda does not derive homiletic interpretations from juxtaposed verses.
ובמשנה תורה מנלן דדריש דתנן נושא אדם אנוסת אביו ומפותת אביו אנוסת בנו ומפותת בנו רבי יהודה אוסר באנוסת אביו ומפותת אביו
§ And from where do we derive that Rabbi Yehuda does derive homiletic interpretations in Deuteronomy? As we learned in a mishna: A person may wed a woman raped by his father and one seduced by his father, despite the fact that his father’s wife is forbidden to him. Similarly, he may marry a woman raped by his son and one seduced by his son. Although one is prohibited by Torah law from marrying the wife of his father or the wife of his son, these prohibitions do not apply to a woman raped or seduced by them. And Rabbi Yehuda prohibits him from marrying a woman raped by his father and a woman seduced by his father.
ואמר רב גידל אמר רב מ"ט דרבי יהודה דכתיב (דברים כג, א) לא יקח איש את אשת אביו ולא יגלה כנף אביו כנף שראה אביו לא יגלה
And Rav Giddel said that Rav said: What is the reason for Rabbi Yehuda’s opinion? As it is written: “A man shall not take his father’s wife, and shall not uncover his father’s skirt” (Deuteronomy 23:1). The latter expression: “And shall not uncover his father’s skirt,” is referring to a skirt that has been seen by his father, i.e., any woman who has had relations with his father may not be uncovered by his son, meaning that his son may not marry her.
וממאי דבאנוסה כתיב מעילויה דקרא דכתיב (דברים כב, כט) ונתן האיש השוכב עמה לאבי הנערה חמשים כסף וסמיך ליה לא יקח איש וגו'
And from where is it known that the verse is written with regard to a woman raped by his father? It is from the previous verse, which deals with the halakhot of rape, as it is written: “And the man who lay with her must give the maiden’s father fifty shekels of silver” (Deuteronomy 22:29), and juxtaposed to it is the verse: “A man shall not take his father’s wife and shall not uncover his father’s skirt.” This shows that Rabbi Yehuda does derive homiletic interpretations from juxtaposed verses in Deuteronomy.
ורבנן אי הוה סמיך ליה כדקאמרת השתא דלא סמיך ליה (דכתיב לא יקח איש את אשת אביו בנתים)
§ The Gemara asks: And how do the Rabbis, who disagree with the opinion of Rabbi Yehuda, respond to this argument? They say: If the two verses were fully juxtaposed, it would be interpreted as you said. However, now that it is not properly juxtaposed, as it is written: “A man shall not take his father’s wife,” in between the halakhot of rape and the pronouncement with regard to uncovering one’s father’s garment, this serves to break the juxtaposition.
בשומרת יבם הכתוב מדבר ולעבור עליו בשני לאוין
Consequently, this particular verse concerning the uncovering of one’s father’s garment is speaking of a woman waiting for her yavam, in this case one’s father. In other words, the yevama of a father who is waiting for levirate marriage to the father is already considered “his father’s skirt,” and she is therefore forbidden to the son. Although this woman who is awaiting levirate marriage is in fact his uncle’s wife and explicitly prohibited to him in any case, this passage comes to teach that he violates two prohibitions. In other words, were he to engage in relations with her he would be penalized both for relations with his uncle’s wife and relations with “his father’s skirt.”
ובמשנה תורה מאי טעמא דדריש איבעית אימא משום דמוכח ואיבעית אימא משום דמופני
§ The Gemara asks: But as Rabbi Yehuda does not generally derive homiletic interpretations from juxtaposed verses, what is the reason that he derives these interpretations in Deuteronomy? The Gemara responds: If you wish, say that it is because it is evident from the context; and if you wish, say instead that it is because this verse is extraneous and is therefore free for this inference.
איבעית אימא משום דמוכח דאם כן לכתביה רחמנא גבי עריות ואיבעית אימא משום דמופני דאם כן לכתוב רחמנא לא יקח איש את אשת אביו לא יגלה כנף אביו למה לי
The Gemara elaborates: If you wish, say it is because it is evident; as, if it is so that the verse did not intend to teach by juxtaposition, let the Merciful One write this halakha prohibiting marriage to a father’s wife alongside the other women with whom relations are forbidden, in Leviticus. Since this verse is out of place, it is certainly coming to teach by way of juxtaposition. And if you wish, say instead that it is because this verse is free, as, if it is so that the verse is not coming to teach an additional halakha, let the Merciful One write only: “A man shall not take his father’s wife.” Why do I need the phrase: “And shall not uncover his father’s skirt”? This phrase is superfluous, and therefore it teaches by juxtaposition.