Resources for Yevamos daf 121
1. The משנה says that if a person disappeared in מים שאין להם סוף, his wife cannot remarry since we are afraid the man emerged somewhere else and we did not see. However, the גמרא on עמוד ב clarifies that this is only a דין לכתחילה but בדיעבד if she remarried we wouldn’t make her get divorced. In fact, the מהר"ם מרוטנבורג says she is supposed to sit shiva immediately upon hearing that her husband disappeared in מים שאין להם סוף even though she cant get remarried based on this information. The reason is that this is all a חומרא דרבנן since מן התורה we should have gone with רוב which would tell us that the person drowned. תוספות in ד"ה ולא היא adds that even if the person who died was famous enough that if he had survived we would have heard of it, we still can’t let her remarry. That means even two רובs don’t help. However, the פּתחי תשובה in אבן העזר סימן י"ז אות קל"ג brings from הגר"ח מוולאזזין that there was a man who fell off a bridge onto a frozen river who disappeared where he allowed the wife to get married because there were two רובs: מים שאין להם סוף and most people die when they fall from that high onto ice. This would seem to be against our תוספות. The באר יצחק in אבן העזר סימן י"ח ענף י answers that תוספות’s two רובs don’t occur at the same time. Therefore, since we have a rule that two ספקות don’t become a ספק ספיקא if they don’t come at the same time, the same is true for two רובs. The חזון אי"ש in הלכות אישות סימן ל"א answers that תוספות’s case is not a case of two רובs that indicate death per se. Rather, one (מים שאין להם סוף) says he died and one (the fact that we didn’t hear that he survived) says it should count as testimony that he died. Despite this חילוק the חזון אי"ש says we can’t invent new היתרים like two רובs if the גמרא doesn’t mention them. Rav Moshe זצ"ל in אגרות משה אבן העזר חלק א סימן מ"ג says based on a חתם סופר in סימן מ"ח that that the reason we can’t use רב אשי’s רוב by a תלמיד חכם to assume we would have heard if he survived because of לא פּלוג. However, nowadays that applies to everyone since not hearing from someone for years when it is so easy to write a letter or make a phone call is a very strong רוב that he died. Therefore, there is no לא פּלוג and we can be מקיל. He is also מחדש in that תשובה that we are only מחמיר by מים שאין להם סוף because of a תקנת חז"ל, so we shouldn’t apply it to other cases which have a strong חילוק. He is מחדש that perhaps חז"ל only made a תקנה where it is usually relevant to a single person, but in another case where it is relevant to the masses they wouldn’t have been גוזר. Based on the two סברות mentioned above (and other סניפים) he allowed the עגונות whose husbands had been sent to Auschwitz and never heard from again to get remarried since it is a very strong רוב that they died and is relevant for the masses.
2. The גמרא says that if we find a man who had his leg chopped off מן הארכובה ולמעלה we can be מעיד that he died since in הלכות טריפות an animal in that state would be a טרפה and die soon. The ריטב"א and others bring the ירושלמי that says this means the woman can get married after twelve months since a טרפה can live twelve months. The קרן אורה points out that the רי"ף and רמב"ם didn’t mention this requirement so it would seem they hold you don’t need to wait twelve months. The חזון אי"ש in יו"ד סימן ה says that nowadays we know that people can survive injuries like that so even though we would still consider the animal a טרפה it would not work to be מתיר an אשה today. The reason is because דיני טרפה were paskened by רבינא ורב אשי and even if the מציאות changes it’s still אסור. Rav Moshe זצ"ל in אגרות משה אבן העזר חלק ב סימן ג says almost exactly the same thing. He says that only by הלכות אכילה do we have a set הלכה that whatever was the מציאות at נתינת התורה is what the הלכה is. However, by all other הלכות of this nature it changes with the times.
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