Study Guide Yevamot 7 Today’s daf is sponsored by Betsy Mehlman in loving memory of her father Harold Mondshein, Zvi Menachem Mendel ben Shlomo on his 38th yahrzeit. “He was a kind, loving man with an optimistic outlook on life and a baal koreh with a beautiful voice."  Today's daf is sponsored by Julie Landau in loving memory of Melvin Landau. "My father loved all kinds of learning and knew something about every topic. He never hesitated to help those in need. Twelve years on, he is sorely missed." Today's daf is sponsored in honor of Naomi Cohen on her birthday. "Happy Birthday from all your family in celebration of your birthday but also to celebrate your dedication to Talmud study and general Jewish knowledge." Rav Shimi suggests that the reason that a drasha was needed to teach that one cannot light a fire on Shabbat even to administer a court related punishment was because it could have been derived from a kal va’chomer that it would override Shabbat. What is the kal va’chomer? The braita which in the end teaches that one cannot administer court death penalties on Shabbat is explained both according to the interpretation on 6b that without the drasha, one would have assumed it was permitted as a positive commandment overrides a negative one even when it is punishable by karet, and according to Rav Shimi’s explanation. After not being able to find a conclusive source to learn that a positive commandment overrides a negative commandment, even when punishable by karet, the Gemara continues to search for a reason for why if there wasn’t a drasha, we would have assumed that yibum could be performed even if it meant a man marrying his wife’s sister. One suggestion is that since yibum overrides the prohibition to marry one’s brother’s wife and that is singled out, we can apply the principle that if something is singled out, it comes to teach about the whole group. This, however is rejected as the general rule is by a prohibition and it is singled out by yibum to permit it. That is not the typical use of a generalization and a detailed case. Another suggestion is the one’s brother’s wife would serve as the paradigm for all forbidden relationships – since yibum overrides that, it would then override all the others. That suggestion is rejected as well as all yibum situations are with the brother’s wife, but if one would permit another forbidden relationship, it would permit two forbidden relationships. Why don’t we say, since it was permitted for the brother’s wife, we can permit everything as is the case by a leper whose eighth days falls on erev Pesach and he has a seminal emission that day – since he was permitted that day to put his hands, ears and toe into the azara as a leper, he is permitted to do it as well, even though he had a seminal emission. But is this really a fair comparison?