Resources for Yevamos daf 69
1. The גמרא asks how we know that a woman who was נבעלת to חייבי לאווין is פּסולה לכהונה with just ביאה alone without קידושין? The גמרא answers that we learn it from אלמנה לכהן גדול where it says לא יחלל זרעו which is משמע just ביאה. The ערוך לנר in ד"ה האי נמי brings theרמב"ם in הלכות מאכלות אסורות פּרק י"ז הל׳ א that says that for all איסורי כהונה (e.g. כהן לגרושה), you are only חייב מלקות if there is a קידושין in addition to the ביאה. He asks that if this is true, why does our גמרא learn from אלמנה לכהן גדול that all חייבי לאווין only need ביאה when אלמנה לכהן גדול is really the exception and we could learn from every other איסור כהונה that you do require קידושין? He answers that since the words of לא יחלל are written by a כהן גדול, it makes sense to interpret it based on the הלכות of a כהן גדול. The קובץ הערות in סימן מ"ה אות ה׳ ולהלן brings a similar question on the רמב"ם from the ר"ש. The ר"ש asks that if the רמב"ם is right that there is no איסור of איסורי כהונה without a קידושין except for אלמנה לכהן גדול, then how can we learn from אלמנה לכהן גדול that all פּסולין only need ביאה to make a woman פּסולה לכהונה when we know אלמנה לכהן גדול is the exception and most חייבי לאווין would not violate any איסור without קידושין! The קובץ הערות has a stunning answer: he says that whether there is an איסור or not has nothing to do with whether a woman is נפסלת. It is only the פּסול itself that causes the woman to be פּסולה. For example, a שחוף (someone who can’t be מקשה) is פּוסל בביאתו even though a משמש באבר מת is פּטור. The reason is that it’s not the איסור that causes the פּסול but rather the ביאה מפּסול. He brings the משנה למלך who is מסופּק whether a ישראל הבא על פּסולי קהל will פּסול her משום זונה. He suggests that it won’t because of the principle of אין איסור חל על איסור. However, רב אלחנן זצ"ל brings רש"י at the very beginning of the sixth פּרק who says that a ישראל who is הבא על הממזרת doesn’t make her פּסול since he isn’t פּסול. רב אלחנן זצ"ל says that this רש"י is a proof to his יסוד that it isn’t the איסור that causes the פּסול but rather any ביאת פּסול is פּוסל and if the person isn’t פּסול then the fact that it is אסור doesn’t cause a פּסול. This would have a fascinating ramification in terms of a case of עשה דוחה ל"ת. In other words, in a case of a woman who falls to יבום to one of the חייבי לאווין, we would say עשה דוחה ל"ת. However, it should still come out that the woman becomes פּסול through their union since even though there is no איסור, the man is still a פּסול.
2. The גמרא says that a fetus less than 40 days since conception is considered מיא בעלמא and not a fetus at all. This has far reaching ramifications. One is that a woman who had a miscarriage within 40 days and then gave birth would still have a פּדיון הבן. A second is that the ש"ך in חושן משפּט סימן ר" ס"ק ב says that even if you hold you can be מזכה to an עובר, you cant be מזכה to one less than 40 days old. However, the most significant one is that of an abortion. The שרידי אש in חלק א סימן קס"ב says that based on our גמרא, if the doctors say that a woman is going to have a child who is going to be disabled or sick and the woman wants to terminate the pregnancy withing 40 days of conception, she may. The שו"ת אחיעזר חלק ג סימן ס"ה at the very end also says that within 40 days it’s not דאורייתא. However, Rav Moshe Feinstein זצ"ל in אגרות משה חושן משפּט חלק ב אות ס"ט is very מחמיר about it and considers it רציחה.
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