Yevamos - Daf 55
- The source that the issur of אשת אח applies to both paternal and maternal brothers
After the Gemara learns that the issur of אחות אשתו – one’s wife’s sister, applies to both the paternal or maternal sister, and derives this from the issur of אשת אח – one’s brother’s wife, it asks for the source that the issur of אשת אח applies to both the paternal and maternal brother. It brings a Baraisa that taught the passuk, "ערות אשת אחיך לא תגלה” – the ervah of your brother’s wife you shall not uncover, בין מן האב בין מן האם – applies whether one’s husband is the paternal or maternal brother. The Baraisa questions whether this is conclusive since on one hand the issur of אשת אח can be compared to the issur of one’s sister, which applies to both a paternal or maternal sister, while on the other hand it could be compared to the issur of one’s father’s brother’s wife, which only applies to a paternal brother. The Baraisa concludes that the passuk ends with the words: "ערות אחיך הוא" – she is the ervah of your brother, to teach that one’s brother’s wife is forbidden whether her husband is the paternal or maternal brother.
- Why kares was mentioned by the issur of אחותו
The Gemara asks that since the Torah learns from one passuk that all arayos receive kares, אחותו דכתב בה כרת למה לי – Why is there a mention of kares by the prohibition of having relations with one’s sister, and answers that is needed for what Rebbe Yochanan said: שאם עשאן כולם בהעלם אחת חייב על כל אחת ואחת – that if one committed all of the ervah transgressions during one lapse of awareness, he is chayav to bring a chatas for each transgression. The Gemara clarifies that according to Rebbe Yitzchak who learns that the reason אחותו was singled out is to teach לדונו בכרת ולא במלקות – that one who has a relations with an issur kares is punished with kares and not with malkus, he learns out to separate the arayos so that they each are chayav a chatas if performed in one lapse of awareness from "ואל אשה בנדת טמאתה – and a woman in her niddah state of tumah you shall not approach. Why did the Torah add a woman? לחלק על כל אשה ואשה – to separate and make one chayav a chatas for each forbidden woman.
- Why שכבת זרע was mentioned in the case of a sotah
Rava asks, that since in basically all cases, העראה, the initial stage of relations, has the same status as the completion of the act, why did the Torah write the words "שכבת זרע", - cohabitation with seed, which refers to the completion of relations, in three cases of a שפחה חרופה – a designated maidservant, a married woman and a sotah? After explaining the reasons for the mention regarding a שפחה חרופה, and a married woman, the Gemara address the sotah and brings a Baraisa which taught that the reference to שכבת זרע is to exclude something from the laws of the sotah. Rava said the Baraisa is coming to exclude שקינא לה דרך אברים – to exclude the case where one warned his wife against bodily contact with another man. Rashi says this refers to pressing oneself against a woman. This type of warning would not make her a sotah. The Baraisa needed to teach this for one might have thought, בקפידא דבעל תלה רחמנא – that the Torah made the matter dependent on the husband’s objection, and in this case the husband objects to bodily contact. Therefore, the Torah teaches that a sotah warning is only valid if it deals with adulterous behavior which is at least the beginning of cohabitation.
