Resources for Yevamos daf 79
1. The גמרא says that דוד המלך had to choose seven descendants of שאול to give over to the גבעונים to kill. He placed them before the ארון and the ארון chose the people to be given over (the ריטב"א explains that the ones chosen were מחויב מיתה anyway). דוד davened that מפיבושת not be chosen. The גמרא explains that if the ארון had already chosen מפיבושת then דוד could not have davened that מפיבושת be released because וכי משוא פּנים יש בדבר? The מהר"י בן לב who is quoted by the ש"ך in חו"ם סימן קס"ג ס"ק י"ח and the באר היטב there in אות ל"ד discusses a question that was unfortunately prevalent during the holocaust: if the government is going to choose two Jews to ח"ו do harm to and you have a connection with a government official and arrange for them to choose anyone but your brother, are you allowed to intervene to have them choose another Jew instead of him? He says that we see from our גמרא that you are allowed to save your brother but only if he hasn’t been chosen by the government already. However, if he has already been chosen then you can’t try to get them out just as we see thatדוד could not have davened to save מפיבושת if the ארון had already chosen him. However, he clarifies that if it isn’t clear that other Jews will definitely be taken, then one can try to save the brother since perhaps no one will be taken in the end. There is also a proof brought by the שו"ת פּעולת הצדיק in חלק ג סימן קנ"ט from the ירושלמי that says that if water is about to enter my field and ruin it I am allowed to move the pipe away from my property even though it will lead the water to your property. However, once the water has come I can no longer move the pipe away.
The ערוך לנר asks on the גמרא that he doesn’t understand what דוד’s davening counted as—if davening for someone counts as doing something, then why was דוד allowed to daven that מפיבושת should be saved (וכי משוא פּנים יש בדבר)? And if it isn’t counted as דוד doing anything but rather it is Hashem doing it, then why cant דוד daven even after מפיבושת was chosen? He answers that the גמרא was not asking וכי משוא פּנים יש בדבר on דוד but rather on Hashem. The גמרא says elsewhere that there is no "משוא פּנים" after the גמר דין. If so the גמרא was asking how could Hashem have listened to דוד after מפיבושת was chosen if that is after גמר דין!? The גמרא answered that Hashem listened to דוד before the גמר דין and didn’t choose מפיבושת. The ערוך לנר points out that if the גמרא reads like he suggested then the מהר"י בן לב has no proof from our גמרא since according to the ערוך לנר the issue was not whether you can try to save someone but rather will Hashem do משוא פּנים after the גמר דין.
2. The גמרא says that they left the bodies of the people who the גבעונים killed for a long time instead of burying them right away. This was allowed because מוטב שיעקר אות א׳ מן התורה ולא יחלל וכו. The ראשונים seem to understand that this wasn’t really an עקירה. The question is why not. The רמב"ן writes that the only time the איסור בל תלין את המת applies is if ב"ד killed the person themselves. However, if someone else killed them then it doesn’t apply. The ריטב"א suggests that it was a הוראת שעה. Theמהר"ץ חיות explains that רמב"ם inהלכות מלכים פּרק ג׳ הל׳ י׳ seems to understand that it was permissible מדין מלך. Meaning the רמב"ם writes there that the king has the right to kill whomever he wishes and leave their bodies around in order to scare the רשעי עולם. The מהר"ץ חיות explains that theרמב"ם must have learned this from our גמרא.
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