Resources for Yevamos daf 29
1. The משנה says that if one of the brothers does מאמר to his יבמה and then her sister falls to him to יבום, then according to ב"ש he can do יבום to the woman he did מאמר to and her sister is מותרת לשוק without any חליצה. There is a מחלוקת ראשונים as to how מאמר works according to ב"ש. רש"י on עמוד ב in ד"ה השתא ארוסה says that מאמר is only דרבנן even according to ב"ש. The difficulty with that פּשט is, as תוספות in ד"ה ב"ש asks in the name of the ריב"ם, that if מאמר is only דרבנן, how could it פּטור the צרה on a דאורייתא level without חליצה? תוספות suggests for רש"י that perhaps רש"י learned that the משנה meant that after יבום is completed the sister is מותרת לשוק without חליצה. However, תוספות himself disagrees and says that מאמר is קונה even מדאורייתא.
Within שיטת רש"י, there is a מחלוקת ראשונים as to what he meant. The רשב"א in ד"ה השתא says that רש"י didn’t really mean it’s only דרבנן because otherwise it couldn’t possibly פּטור the צרה. Rather, he meant that it isn’t a full קידושין דאורייתא but rather it begins the קידושין but isn’t גומר the קידושין. However, רבינו פּרץ says that רש"י meant what he said and it’s only דרבנן. As to תוספות’s question about how the sister could be מותרת לשוק without חליצה if the מאמר was only דרבנן, he suggests an incredible חידוש. He says that since מאמר looks like a real marriage, the sister looks like an אחות אשה. Therefore, since חז"ל didn’t want people to think that קידושין would be תופס by אחות אשה they were עוקר the קידושין of the deceased brother retroactively, despite the fact that he is dead! Therefore, since there was no marriage of the second woman to the deceased brother, she obviously didn’t fall to יבום and doesn’t need חליצה. On a side note, this answers a powerful question of the ערוך לנר. The ערוך לנר asks that as we know, ב"ש allows a צרת ערוה to do יבום. That he means he must learn the דרשה of לצרור like ר"ש (as the גמרא on דף ח ע"ב hints to and תוספות on דף י"ג ע"ב sounds like). If he learns like ר"ש, that means that two sisters that fell to יבום together should be עריות to each other מדאורייתא which means both should be מותרת לשוק without חליצה! If so, how could ב"ש have said "אשתו עמו" and he can stay married to the בעלת מאמר? She is an ערוה to him! However, according to רבינו פּרץ, חז"ל were עוקר the original קידושין because of the מאמר that was done so the second sister never fell to יבום at all. As such, the first woman is not an ערוה even according to ר"ש.
Within שיטת תוספות that מאמר according to ב"ש works מדאורייתא, there are two ways of understanding that מאמר. The קובץ הערות in סימן ל"ה אות ז explains that our תוספות holds that מאמר according to ב"ש is a תחילת יבום but not the full יבום. Therefore, even the woman who received מאמר is not fully מתיבמת and will need חליצה in addition to her גט in order to be מותרת לשוק. However, תוספות ישנים in אות ב argues on תוספות and says that מאמר works as a קידושין מדאורייתא but does not affect זיקה at all. Therefore, the reason the בעלת מאמר needs a חליצה in addition to her גט is because the מאמר did not affect the זיקה since it was only בתורת קידושין. Therefore, the קובץ הערות is left with a question that if according to the תוספות ישנים the מאמר is only a קידושין, who did it make her אסור to? She was already אסורה as a יבמה לשוק to everyone! You cant have a קידושין that makes her אסור to no one. However, if you learn like תוספות that מאמר is התחלת יבום then you don’t have this question since the מאמר slightly removed the זיקה so she was slightly מותרת and the מאמר makes her an אשת איש on that small amount.
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