1. Reish Lakish: Rebbi taught in a Mishnah, the
sister of one's divorcee is forbidden mid'Oraisa,
the sister of one's Chalutzah is forbidden
mid'Rabanan. 40b
QUESTION: since the opinion above (and RASHI explanation there) it has to be the contrary because the "forbidden mid'Rabanan" needs HIZUK!! -
why dosen't we say that here as we learned at (??? - could you remind me where?) yevamot, formerly?2. 41a - rav hamnuna brought the mishna: 3 brothers, 2 are
married to sisters, one is single. A married brother
died, the single brother gave a Ma'amar to the
Yevamah; then the other married brother died, then
his wife died; the Yevamah does Chalitzah, not
Yibum.
QUESTION: if the single brother had done KIDUSHIN (not just ma'amar) - is it different? If so - what is the different? If not - what about BITH
SHMA'I - which said that m'aamar is KINYAN, and make ZIKAH like KIDUSHIN- why can't we stand the case in kidushin ?1. You are referring to the Gemara earlier on 36b and elsewhere. However, we find often that the Rabanan do not always make additional Gezeiros in order to give Chizuk to their initial Gezeiros. Indeed, in the Gemara earlier on 36b, the Gemara was not sure whether we apply that principle. Here, too, the Gemara (top of 41a) gives a logical reason why it should not apply.
2. There is no such thing as Kidushin with a Yevamah. By definition, Kidushin with a Yevamah is Ma'amar.
Regarding what Beis Shamai would say in such a case, TOSFOS (DH Asah Bah) answers your question and says clearly that this Beraisa is arguing with Beis Shamai, because according to Beis Shamai, Ma'amar makes a complete Kinyan, and thus he could continue and do Yibum with her and the second sister that fell toYibum could not prohibit the Yevamah.
Yisrael Shaw