Resources for Yevamos daf 77
1. The גמרא says that דואג said that עמוני ומואבי ladies should not be allowed to marry in to the Jewish people since they should have at least brought the Jewish ladies food in the desert. At that point יתר הישמעאלי got up and said he had a קבלה from the ב"ד of שמואל that עמוני ולא עמונית, מואבי ולא מואבית. The Brisker Rav in the חידושי הגרי"ז על התורה in the section about מגילת רות asks what did יתר הישמעאלי add that had not been said by אבנר? The ב"ד was ready to be פּוסל דוד because of דואג’s question so why was it better when יתר הישמאלי said it? He answers that there are two ways that the ב"ד הגדול paskens. One is by making דרשות using the י"ג מדות שהתורה נדרשת בהם. The second way is if they have a מסורה of a הלכה למשה מסיני. The רמב"ם in הלכות ממרים פּרק ב הל׳ א says that if ב"ד paskens something based on their own דרשה, a later ב"ד can come along and revoke the earlier ב"ד’s פּסק and issue a new פּסק. However, he says in הלכות ממרים פּרק א הל׳ ג that when it come to a הלכה למשה מסיני there cannot be a מחלוקת so an earlier פּסק about a הלכה למשה מסיני would never be rescinded. Therefore, the Brisker Rav suggests that אבנר was saying a דרשה that he had made using the י"ג מדות שהתורה נדרשת בהם. Therefore, when דואג had an unanswerable question on the דרשה, the ב"ד at that time was prepared to throw it out. When יתר הישמאלי came, he had a מסורה from שמואל which sounded like a הלכה למשה מסיני. On that there can be no questions and it can’t be rescinded.
2. The גמרא says that if someone says over a הלכה בשעת מעשה that was never heard before, it cannot be accepted. תוספות qualifies that this is only if the person saying it is נוגע בדבר. The ריטב"א adds that this doesn’t apply to someone saying a הלכה who brings סברות and proofs to what he is saying. It only applies to where someone says over something as a קבלה מרבו where we are concerned that he will not remember it exactly correctly when he is under the gun (unless his Rebbe is still alive like שמואל ובית דינו). The גמרא on דף צ"ח brings another exception. If the person says over a הלכה that is relevant now along with a הלכה that is not relevant now, we believe him on both since we assume it was the same קבלה and as רש"י says there, “נכרים דברי אמת דביחד קבלן”. The חתם סופר asks a question based on this which becomes a strong question on our גמרא. in תורת משה at the end of פּרשת בשלח, the חתם סופר asks how was בועז believed about רות when he said עמוני ולא עמונית, מואבי ולא מואבית? Didn’t he have the same issue of not being able to believe someone when it is בשעת מעשה? He answers that since בועז said עמוני ולא עמונית as well which wasn’t relevant to him at that time, he was also believed about מואבי ולא מואבית. If that is true, then we have a question on our גמרא. Why wasn’t יתר הישמעאלי believed for the same reason? He also said both הלכות! it would seem that when our גמרא asked the question on יתר הישמעאלי, it could have answered with that exact answer but had a better answer that שמואל ובית דינו are still alive.
3. The גמרא says that the reason the בנות מואב were not to blame for not bringing food was because כל כבודה בת מלך פּנימה. The מהרש"ם in שו"ת מהרש"ם חלק ב במפתחות ליו"ד סימן ס"ג asks why the women were to blame if their husbands did not want them to bring food--we have a principle of מה שקנתה אשה קנה בעלה, so it wasn’t the wives food to offer? He answers that we see from here that the concept of מה שקנתה אשה קנה בעלה doesn’t apply to נכרים.
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