Resources for Yevamos daf 30
מראה מקומות
1. The משנה tells us that in the case where a woman fell to יבום and was an ערוה on one of the brothers but by the time she falls a second time to יבום she is no longer and ערוה since her sister has since died, the remaining brother will be אסור ליבם her since she was נאסרה שעה אחת. The תוספות in ד"ה ונאסרה points out that even if you hold נישואין מפּילים, in a case where the ערוה was an ערוה when she was married but by the time she fell to יבום the first time she wasn’t an ערוה anymore (e.g. if one of the sisters died before the other sisters husband died so the אחות אשה was gone prior to the נפילה ליבום) we would not say נאסרה שעה אחת. The reason for this is that נישואין מפּילים is only relevant to creating a צרת ערוה. In חידושי מרן רי"ז הלוי in הלכות יבום, the Brisker Rov explains this concept as follows: it is only at the time of the actual שעת נפילה that we say “כל יבמה שאין אני קורא בה בשעת נפילה יבמה יבא עליה נאסרה עולמית”. However, when it comes to defining the שם of צרת ערוה, that happens at the time of marriage as the צרת ערוה is an איסור ליבום that is defined at the time of marriage. Therefore, even if the woman who is the ערוה got divorced or died prior to the נפילה ליבום, the צרה will still has the status of צרת ערוה.
In קובץ הערות, סימן ו׳ אות ד, רב אלחנן ז”ל points out that the תוספות mentioned above says that if two brothers marry two sisters and one sister dies and then the husband of the other sister dies and she falls to יבום, she is eligible to do יבום even if you hold נישואין מפּילים. רב אלחנן ז”ל says it is פּשוט that even if that sister who falls to יבום has a צרה, they both could do יבום since she can’t be more חמור than the ערוה herself. If so, he asks why this would be different than the case of two brothers married to two sisters where one of the brothers has a צרה and we said that if the sister who has a צרה dies prior to the נפילה ליבום her צרה is still considered a צרת ערוה if you hold נישואין מפּילים. Why should it matter which sister dies? He answers that in the case where the sister who has a צרה stops being an אחות אשה because her sister died, then the צרה is not a צרת ערוה anymore since the whole ערוה doesn’t exist anymore. However, if the brother merely divorced the sister (or she died), the שם ערוה itself didn’t disappear while the sister was around.
In an earlier דף we mentioned the ספק of the אתוון דאורייתא in סימן ח׳ as to whether the איסור יבמה לשוק was based on the אישות of the dead brother continuing on a smaller level or is it a new אישות the תורה created for the living brother. If the latter was true, is it a real דין אישות which carries a יהרג ואל יעבר or is it just a לאו? The דברי יציב in אה"ע סימן ק"י says it’s תלוי whether you hold מיתה מפּלת or נישואין מפּילים. If you hold מיתה מפּלת then it’s a new אישות but if you hold נישואין מפּילים then it must a continuation of the pre-existing אישות of the brother. However, the way רב אלחנן ז”ל ז"ל explained the idea of נישואין מפּילים in קובץ הערות, סימן ו׳ אות ג, it may not be a ראיה since all נישואין מפּילים means is that the reason for the נפילה is the נישואין and that is what is קובע the שם צרת ערוה.
2. When the משנה says “הרי זו נאסרה עליו שעה אחת”, the simple understating of that is that both the sister and the "נכרית" are אסורות: the sister as an ערוה שנאסרה שעה אחת and the נכרית as her צרה. This is also the opinion of תוספות in ד"ה ונאסרה. However, the רמב"ם in the פּירוש המשניות says something that is quite surprising. He says that he is מסופּק whether a woman who was נאסרה שעה אחת is an איסור דאורייתא or just an איסור דרבנן like a שנייה! Since the צרה of a שנייה can even do יבום, therefore the צרה should at least do חליצה מספק. The רש"ש asks that according to that theרמב"ם should say that the ערוה herself needs to do חליצה as she may only be a שנייה which would require חליצה, and it doesn’t sound like that at from his לשון. He also quotes the רעּ"ב in משניות who is clear the only question is whether the צרה needs חליצה but not the ערוה. He doesn’t give an answer.
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