Resources for Yevamos daf 110
1. The גמרא says that if a person steals away a קטנה who was married from under the חופּה and gives her קידושין that the חכמים were עוקר his קידושין. The תוספות here in ד"ה לפיכך and the תוספות in ב"ב דף מ"ח ע"ב ד"ה תינח are מסופּק what the mechanics are for the עקירת קידושין: is it because the חכמים have a power to be עוקר דבר מן התורה, or is it the fact that they have the ability to be עוקר קידושין via הפקר ב"ד הפקר? The ריטב"א inכתובות דף ג ע"ב ד"ה תינח adds a third possibility—that all people are מקדש אדעיתיה דרבנן. Therefore, the חכמים can be עוקר anything since it is as if the person said that he only wants his קידושין to be חל on condition that the חכמים approve. The ראשונים ask that according to either the פּשט that the חכמים can be עוקר דבר מן התורה or that people are מקדש אדעיתיה דרבנן, how would you explain the גמרא’s next question ofתנח דקדיש בכספּא קדיש בביאה מאי? If the point is that people are תולה their קידושין on someone else’s דעת or that the חכמים can be עוקר דבר מן התורה then what difference does it make how they were מקדש? תוספות in ב"ב answers that the reason קידושין של ביאה are worse is that surely the רבנן would not agree to be עוקר the קידושין if it would result in an עברה like all the ביאות are ביאת זנות. The קמ"ל is that they would in that case. The ריטב"א mentioned above asks (by implication) why the גמרא doesn’t ask about קידושי שטר? He answers that based on the way we just explained the גמרא it makes sense since the חכמים have the power to be עוקר any form of קידושין and the only question was about ביאה since they wouldn’t want to cause an עברה through their הפקעת קידושין.
2. תוספות in ב"ב mentioned above asks why we find in many גמרות that the גמרא says the words כל דמקדש אדעיתיה דרבנן מקדש and our גמרא leaves it out? He answers that our גמרא didn’t need that concept since the man did a bad thing by stealing the child bride and forcing her to marry him and the חכמים certainly had the power to be עוקר דבר מן התורה in that case. However, where there was nothing wrong with the קידושין then they can only be עוקר it via כל דמקדש אדעתיה דרבנן. There is an interesting question discussed by the רשב"א in שו"ת הרשב"א סימן אלף קס"ב: If the חכמים have the power to be עוקר קידושין, why wouldn’t they do it in cases of עיגון or in cases of a רשע husband? He brings many proofs that we don’t say it by עיגון but he adds that we don’t say it when the husband is a רשע since even though the person is not כדעת חכמים the קידושין was. In other words, the חכמים can only עוקר the קידושין when the קידושין itself was not אדעתא דרבנן. But if the קידושין was good but the person himself is not acting אדעתיה דרבנן then she is still מקודשת.
3. The משנה says that if two קטנות fell to יבום then יבום or חליצה to either one will be פּוטר the other. There is an interesting אור שמח in הלכות יבום פּרק ה׳ הל׳ כ"ג. He asks that it is possible that after he does יבום to one girl the second girl will get married, get older and be married דאורייתא. At that point the younger sister who did יבום might to מיאון in which case the now older married woman is זקוקה ליבום and אסור on her husband. That would be an issue of דרכי נועם. Why weren’t the חכמים חושש for that? He leaves it צע"ג.
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