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Yevamos 2a: גדר היתר אשת אח ליבום
Yevamos 2a: גדר היתר אשת אח ליבום
Nov 26, 2025
4:09
The Masechta opens by listing close relatives with whom yibum is not allowed — including cases of eishes ach (a brother’s wife) outside the mitzvah of yibum. This immediately raises the core question: How can yibum ever work? Yibum is, by definition, marrying an eishes ach, which is normally an issur punishable by kares. Tosfos based on Kovetz He’aros 9 Yibum works through the rule of aseh docheh lo sa’aseh — a positive mitzvah overriding a prohibition. The issur of eishes ach remains fully in place; it is simply overridden in this scenario. Tosafos asks: If yibum overrides ervah, why not apply it to other forbidden relatives, like a wife's sister? Tosafos answers: Yibum is allowed only because the Torah explicitly commands it. The override applies only here, nowhere else. Yad Ramah’s Approach (Sanhedrin 53a): Yibum is not based on aseh docheh lo sa’aseh. Rather, the Torah’s prohibition of eishes ach never applied to a case where yibum is possible. The issur applies only when the woman has children and yibum is off the table. Ramban’s View (Toras Ha’adam): Agrees with the Yad Ramah. Compares it to a kohen becoming tamei for a mes mitzvah: it’s not an exception — that case simply wasn’t included in the original prohibition. So too, eishes ach simply doesn’t apply in a scenario of yibum. Nafka Minas (Practical Differences Between the Views): Kiddushin with a Yevama: Rashi says kiddushin cannot take effect, because the issur of eishes ach still exists (fits with Tosafos/Rav Elchonon). According to Ramban/Yad Ramah, kiddushin might work, since eishes ach isn’t present at all in a yibum case. Yibum for the Wrong Reasons: The Gemara warns it’s like living with an ervah. Rambam says it’s not actually an ervah at all — once the brother dies, the issur disappears. Rambam fits with Ramban: the issur is simply gone in a yibum case. Tosafos/Rashi fit the stricter language of the Gemara — the issur exists but is overridden. This sugya sets up a major theme of Yevamos: Is yibum an override of eishes ach, or is eishes ach simply not present when the Torah commands yibum?