Resources for Yevamos daf 102
1. The גמרא says that if אליהו came and said that you can’t do חליצה with a סנדל we wouldn’t listen to him because the מנהג is to use a סנדל. The ירושלמי here says that the reason is because “מנהג מבטל הלכה”. This ירושלמי needs explanation. Why would מנהג מבטל הלכה be true and when would we apply it? The הלכות קטנות in סימן ט explains it as follows: If the מנהג of כלל ישראל is a certain way then it must be that מן השמים that’s what Hashem wants us to do since Hashem would not allow a practice to take hold as a מנהג in כלל ישראל if it were wrong. The מגן אברהם in סימן תר"ץ ס"ק כ"ה brings that even if most poskim are מחמיר against a מנהג and there is only one is מקיל we would still apply מנהג מבטל הלכה. Rav Moshe ז"ל in אגרות משה in י"ד ג סימן נ"ב אות ג paskens a הלכה based on similar reasoning. He says that one is not required to say ברכת המזון על הכוס even if one ate together with a מזומן and wine is readily available. He explains that despite the fact that most שיטות require bentching על הכוס in this scenario, the מנהג for generations was not to do it. He adds that even though the reason for the מנהג was that people in Europe were too poor to afford wine and now we can afford it, if the מנהג for generations was not to do it its as if כלל ישראל paskened like the minority of שיטות that says we don’t bentch על הכוס. It should be noted that the מרדכי in בבא מציעא סימן שכ"ו says that the concept of מנהג מבטל הלכה only applies if there is some שיטה or ראיה that it is correct, but if there is nothing to be תולה the מנהג on then we would not accept it. The רשב"ש in סימן תקס"ב limits מנהג מבטל הלכה as well and says that it only applies in one of two scenarios: the הלכה that is מחמיר against the מנהג isn’t clear that its actually the הלכה, or by cases of דיני ממונות where common practice can override the הלכה at times. The ירושלמי that applies the rule of מנהג מבטל הלכה to חליצה is just using a borrowed term and it means it looks like it is a case of מנהג מבטל הלכה. The חזון אי"ש in הלכות שביעית סימן ז ס"ק כ"ו brings the ראב"ד who says that it only applies to איסורי דרבנן like being חולץ בסנדל but not by דינים דאורייתא.
Regarding the above גמרא about not following אליהו, theרמב"ם in his הקדמה לסדר זרעים says that the meaning of our גמרא is that a נביא has no ability to change a מצוה based on נבואה. The שדי חמד asks that our גמרא doesn’t say that. Our גמרא says the reason is because כבר נהגו העם לחלוץ בסנדל. He answers that the רמב"ם must have had a different גירסא in our גמרא.
2. The גמרא says that חליצה requires כוונה of both the man and woman and if not it is a חליצה פּסולה. The בית מאיר in אבן העזר סימן קס"ט ס"ק מ"ד says that this is a הלכה למשה מסיני. He also says that when we say כוונה we mean כוונה לצאת המצוה. This is also the opinion of the קצות החושן in סימן ער"ה ס"ק ד. However, the חכם צבי in סימן א and מהרש"ם in ח"א סימן מ"א disagree and say it means כוונה להקנות, meaning כוונה to be מקנה the woman to herself and the woman need s כוונה to be קונה herself. The קצות asks on this שיטה why would the יבם need the כוונה of the woman? You can be מקנה something to someone else without their knowledge via דעת אחרת מקנה! The מהרש"ם answers that the גמרא is מסופּק whether חליצה is something negative for her since once she gets חליצה she can’t do יבום in which case דעת אחרת מקנה wouldn’t work since you can’t give something to someone that they wouldn’t want to have without their knowledge.
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