1) THE LAW DERIVED FROM "ESHES BINCHA"
OPINIONS: The Mishnah (53a) states that one who has relations with his daughter-in-law is liable for transgressing both the prohibition of "Kalaso" ("his daughter-in-law") and "Eshes Ish" ("a married woman"). The Gemara here asks, why does the Mishnah not also mention that he transgresses the prohibition of "Eshes Beno" ("the wife of his son")?
What is the Gemara's question? The prohibition of "Kalaso" is the prohibition of "Eshes Beno"! RASHI (DH v'Nechayev) explains that the verse states, "The Ervah of your daughter-in-law you shall not reveal, she is the wife of your son, do not reveal her Ervah" (Vayikra 18:15). Since the verse goes out of its way to express the same prohibition twice, it apparently intends to give two prohibitions -- "Kalaso" and "Eshes Beno" -- against this single relationship. This is the basis of the Gemara's question, why are both prohibitions not listed in the Mishnah?
Abaye answers that the verse opens with "Kalaso" and concludes with "Eshes Beno" in order to teach that "Kalaso" and "Eshes Beno" are the same thing.
The straightforward words of Abaye's answer does not seem to give a real answer to the Gemara's question. It seems unnecessary for the Torah to reveal that a daughter-in-law is also the wife of one's son. What is the intention of Abaye's answer?
(a) RASHI (DH v'Siyem) explains that the word "Hi" in the verse, "Eshes Bincha Hi" -- "she is the wife of your son," implies that the verse is not teaching a second prohibition. What is the verse teaching? Rashi explains that the verse is teaching that even after the death of the son, his widow remains prohibited to her father-in-law and has the status of "Kalaso."
Rashi's explanation implies that the Gemara, in its question, did not know that the verse of "Eshes Beno" teaches that a daughter-in-law is considered "Kalaso" even after the death of the son. The CHIDUSHEI HA'RAN, however, understands Rashi's intention differently. He understands that the Gemara already knew this teaching in its question. Rather, the Gemara's question was that if the only thing the verse teaches is that the woman is considered "Kalaso" even after the son's death, then the verse should state merely, "Kalaso Hi" -- "she is your daughter-in-law," as the verse says with regard to a man's mother: "Imcha Hi" -- "she is your mother" (Vayikra 18:7), immediately after it says that "Ervas Imcha" is forbidden. Why does the verse change its terminology to "Eshes Bincha"? This change implies that the verse is teaching an additional prohibition. Abaye answers that the mere change in terminology does not imply that "Eshes Bincha" is a new, second prohibition, in addition to the prohibition of "Kalaso."
(b) The Chidushei ha'Ran quotes the RAMBAN who explains the Gemara differently. He says that the verse of "Eshes Bincha" (Vayikra 18:15) is not needed to teach that a daughter-in-law is prohibited even after the son's death. The Torah relates that when Yehudah was informed that Tamar was pregnant, he was told, "Zansah Tamar Kalasecha" -- "Tamar your daughter-in-law was promiscuous" (Bereishis 38:24). The Torah calls her Yehudah's "daughter-in-law" even after the death of his sons who had married her. The Gemara's discussion therefore is straightforward. The Gemara's question was that the Torah seems to be giving two prohibitions, "Kalaso" and "Eshes Beno." Abaye answered that the Torah's intention in the end of the verse is merely to define "Kalaso" by teaching that it means his son's wife.
The Chidushei ha'Ran asks that the same verse which the Ramban cites as a question on Rashi's explanation is also a question on his own explanation. If the Torah already says, "Zansah Tamar Kalasecha," there is no need for another verse to teach what "Kalaso" means! The Chidushei ha'Ran suggests that it is possible that the Ramban means that one indeed might have thought that "Kalasecha" there and "Kalaso" here refer to a bride who is about to be married, but not to the married wife of one's son. It appears that the Chidushei ha'Ran favors the approach of Rashi. (Y. Montrose)

54b----------------------------------------54b

2) REBBI AKIVA'S OPINION: WHICH TAKES PRECEDENCE, "MIKRA" OR "MESORES"?
QUESTION: The Gemara quotes a dispute between Rebbi Akiva and Rebbi Yishmael with regard to the source of the Torah prohibition against passive participation in the transgression of Mishkav Zachur. Rebbi Akiva says that the source is the same verse which states the prohibition against active participation: "A male you shall not lie with, the lying of a woman" (Vayikra 18:22). Rebbi Akiva explains that the phrase "Lo Sishkav" can be read (with a different arrangement of vowels) in the passive form as "Lo Sishachev" -- "do not be lied down." (See HAGAHOS HA'BACH to Rashi.) This reading teaches that the Torah considers passive participation an act of Arayos as well.
This statement of Rebbi Akiva seems to contradict his position earlier in Sanhedrin (4a), where he is listed among the Tana'im who maintain "Yesh Em l'Mikra." "Yesh Em la'Mikra" means that Halachos are learned from the verse based on the way it is read. This is in contrast to "Yesh Em la'Masores," which means that Halachos are learned from the verse based on the way it is written. In the Gemara here, Rebbi Akiva seems to take the approach of "Yesh Em la'Masores," because he derives from the way the word "Sishkav" is written -- "Sishachev" -- the prohibition against passive participation in the sin of Mishkav Zachur. How can Rebbi Akiva apply derive a law from the "Masores" when he maintains that laws are derived only from the "Mikra," the way the verse is read (in this case, "Lo Sishkav")?
ANSWERS:
(a) The YAD RAMAH writes that the correct explanation of the Gemara is as follows. When the Gemara says that the word is read "Sishachev," it means that when the Torah forbids a man from being an active participant in relations with another man, it obviously means also to forbid passive participation as well. The prohibition is not actually derived from reading the word differently, but from logic.
(b) A slightly different answer is given by the CHIDUSHEI HA'RAN. He cites the verse that discusses the actions of the older daughter of Lot who had relations with her father when he was drunk. She proclaimed to her sister, "Shachavti Emesh Es Avi" -- "I lied yesterday with my father" (Bereishis 19:34), even though she was the passive participant. From that verse, it is evident that the verb of "Shachav" is used to connote the passive participant as well.
The author of the footnotes on the Yad Ramah (Zilber Edition, 5760) comments that these explanations seem to differ from the way this discussion is quoted in the Gemara in Kerisus (3a). The Gemara there writes "Sashkiv" -- not only with different vowels, but also with an additional letter Yud in the middle, making it a different word entirely. This implies that Rebbi Akiva's point is that it is considered as though the verse also says "Sashkiv," and not that he means merely to make a logical conclusion from the context of the verse, or that his proof is from the definition of the word as it used elsewhere.
This question is not problematic in light of the Girsa of the SHITAH MEKUBETZES in Kerisus there, who indeed omits the letter Yud from the word. (Y. Montrose)