Resources for Yevamos daf 52

1.      The גמרא discusses how מאמר is done. רש"י in ד"ה ונתן לה says that giving כסף קידושין doesn’t work מדאורייתא by a יבמה since קידושין aren’t תופס by an אשת אח, and the only קנין the תורה allowed was יבום itself. What is unusual about רש"י is that it sounds like the כרת of אשת אח still exists even though she fell to יבום. However, the גמרא earlier on דף י told us that according to ר׳ יוחנן once a woman falls to יבום the כרת של אשת אח goes away permanently and never comes back to any of the brothers (which is why there is only a לאו if two brothers did יבום). Moreover, the גמרא in קידושין asks why a יבמה can be נקנית with כסף and says it is learned out of a פּסוק. So why does רש"י need to give us the explanation of קידושין  not being תופס  by an אשת אח? The קובץ הערות in סימן י ס"ק ג-ד explains our  רש"י based on a חקירה of ר׳ שמעון שקאפּ זצ"ל: by a woman who is an ערוה, is it the כרת that blocks the תפיסת קידושין to her or is כרת just a סימן לחומר הדבר and it is the סיבת האיסור itself that blocks תפיסת קידושין? רב אלחנן זצ"ל explains that רש"י is telling us that it is the סיבת האיסור that prevents תפיסת קידושין. Therefore, in our case, רש"י needs to explain that even if we know from a פּסוק that יבום only works with ביאה, perhaps כסף קידושין can work as קידושין, especially if you hold that קידושין is תופס by a יבמה לשוק. Therefore, רש"י needs to tell us that the even though the כרת of אשת אח is gone, the סיבת האיסור is still there if you aren’t doing יבום and as such the קידושין can’t be חל.

2.      The גמרא asks whether a גט that a יבם asked a סופר to be write before he did יבום and then gave to his wife later is valid. רש"י explains that we are discussing a case where he gave his wife the גט after יבום had been completed. תוספות in ד"ה ליבמתו says that this cannot be as there is no possibility that such a גט could work because it was written at a time when a גט would not have permitted her לשוק so it isn’t considered בידו. Furthermore, what would the גמרא have meant when it said that “perhaps the גט won’t work since he didn’t do מאמר“? מאמר  is only דרבנן! Therefore, תוספות explains that the question is whether this גט even has a ריח הגט to make her פּסול כהונה. The ריטב"א quotes this פּשט and says the simple reading of the גמרא is not like that and therefore gives another פּשט. He says that the issue in general with giving a גט at a time when it isn’t בידו לגרשה is that there is a חסרון in his ability to make a שליח. In other words, until he is the husband, he can’t make the סופר a שליח since he isn’t the husband yet. Therefore, when it comes to a יבמה, he is already connected to her through זיקה, and he consequently enough of a בעל to be able to make a שליח to give a גט even מדאורייתא. When the גמרא said that perhaps this גט doesn’t work since he didn’t do מאמר, the גמרא just meant that perhaps it doesn’t even work מדרבנן to make her פּסול לכהונה. The ריטב"א points out that the major נפקא מינה whether you go like תוספות’s explanation or that of רש"י and the ריטב"א is that according to תוספות the whole question is only relevant on a level of דין דרבנן and according to the of רש"י and the ריטב"א it is a פּסול דאורייתא. Since the גמרא isn’t מכריע this question, the הלכה should be according to תוספות that it works since ספק דרבנן לקולא and according to רש"י and the ריטב"א it should be פּסול since ספק דאורייתא לחומרא.