1)

(a)Rebbi Elazar learns from the Pasuk in Tehilim "Semuchim la'Ad l'Olam Asuyim b'Emes v'Yashar" - the principle of 'Semuchim' (comparing two Pesukim that are juxtaposed (in the same way as we compare two phrases in the same Pasuk under the heading of 'Hekesh').

(b)Rav Sheshes Amar Rebbi Elazar citing Rebbi Elazar ben Azaryah learns from the Semuchim in Ki Setzei ...

1. ... "Lo Silbash Sha'atnez ... Gedilim Ta'aseh Lach" - that Kil'ayim (the mixture of wool and linen) is permitted in Tzitzis (i.e. Techeles [dark blue woolen] threads on a linen garment).

2. ... "Lo Sachsom Shor b'Disho ... Ki Yeshvu Achim Yachdav" (the introductory Pasuk to Yibum) - that if a Yevamah falls before a leper, we do not stop her right to protest. Practically, this means that we force the Yavam to perform Chalitzah, and not Yibum (Rebbi Elazar ben Azaryah).

(c)Rav Yosef says that - even Rebbi Yehudah, who does not learn Semuchim elsewhere in the Torah, concedes Semuchim in Sefer Devarim.

2)

(a)Ben Azai learns from the Semuchim in Mishpatim "Mechashefah Lo Sechayeh ... Kol Shochev im Behemah Mos Yumas" - that in the same way as the latter is Chayav Sekilah, so too, is the former.

(b)We learn that the punishment by Shochev im Behemah is Sekilah from Ov v'Yid'oni - because in both cases, the Torah uses the Lashon "Demeihem Bam".

(c)Rebbi Yehudah disagrees with ben Azai - on the grounds that just because the Torah places Mechashefah next to Shochev im Behemah, this does not justify giving her Sekilah.

(d)Rebbi Yehudah learns Sekilah by Mechashefah - from Ov v'Yid'oni, which are a branch of Mechashefah. Consequently, when the Torah singled them out to give them a Din of Sekilah, the Din extends to all branches of Mechashefah, and not just to Ov v'Yid'oni.

3)

(a)Everyone agrees that a person is permitted to marry the woman whom his son raped or seduced - because "Kalaso" implies specifically the woman whom his son married.

(b)According to the Tana Kama of the Beraisa, a person is permitted to marry the woman whom his father raped or seduced. Rebbi Yehudah however, learns from the Semuchim of "v'Nasan ha'Ish ha'Shochev Imah la'Avi ha'Na'arah Chamishim Kasef ... (Lo Yikach Ish es Eishes Aviv) v'Lo Yegaleh Kenaf Aviv" - that just as the former Pasuk speaks about a case of rape, so too, does the latter case forbid (on the son) the woman his father raped.

(c)Although the Tana Kama Darshens Semuchim throughout the Torah - he disagrees with Rebbi Yehudah on the grounds that, had the Torah meant to compare them, then it would not have interrupted between the two with "Lo Yikach Ish es Eishes Aviv".

(d)According to the Tana Kama "v'Lo Yegaleh Kenaf Aviv" - refers to the Shomeres Yavam of his father.

(e)Even though she is Asur already because of Eishes Achi Aviv - the Torah comes here to add a second Lav.

4)

(a)In any case, we see that even Rebbi Yehudah agrees with Semuchim in Sefer Devarim. One reason for saying this in the previous Derashah is because it is evident - because otherwise (had the Torah merely wanted to add Lavin like the Rabanan maintain), why did the Torah write it here, and not in the Parashah of Arayos?

(b)The other reason is because it is Mufneh (because, having written "Lo Yikach Ish es Eishes Aviv", "Lo Yegaleh Kenaf Aviv" is superfluous).

(c)The Semuchim of Tzitzis is evident, too - because otherwise, why does the Torah write "Gedilim Ta'aseh Lach" here (in Ki Setzei) and not in Parshas Tzitzis in Shelach Lecha?

(d)We retract from the suggestion that it is also Mufneh (because, having written in Kedoshim "u'Veged Kil'ayim Sha'atnez Lo Ya'aleh Alecha", why does the Torah need to repeat "Lo Silbash Sha'atnez" in Ki Setzei?) on the grounds that both Pesukim are needed. The Torah needs to write ...

1. ... "Lo Silbash Sha'atnez", because, had it only written " ... Lo Ya'aleh Alecha" - we would have thought that Sha'atnez is forbidden in any way that he wears it, even as a salesman to demonstrate what he is selling (even though he is gaining no direct benefit from it). Therefore the Torah needed to teach us that he is only Chayav if he puts it on in order to benefit from its warmth, which is the reason that one generally wears clothes (though it is unclear why one requires specifically the Hana'ah of warmth, and not of being covered for reasons of modesty - see note at end of 2.).

2. ... " ... Lo Ya'aleh Alecha", because, had the Torah just written " ... Lo Silbash Sha'atnez" - we would have thought that one is only Chayav for wearing the garment, where the benefit is considerable, whereas just putting it on top of oneself, where the benefit is minimal, is permitted. Therefore the Torah forbade even Ha'ala'ah. Note: This distinction only makes sense if the benefit in question is that of warmth, but not if we include being covered - see question at end of 1.

5)

(a)It is not "Lo Silbash Sha'atnez" that is Mufneh, we conclude, but "Tzemer u'Fishtim Yachdav", according to Tana d'Bei Rebbi Yishmael, who learns that only a woolen or linen garment is called 'Beged' - from the Pasuk in Tazri'a (in connection with Nega'im) "b'Veged Tzemer O b'Veged Pishtim".

(b)We think that "Tzemer u'Fishtim" is not really Mufneh - by establishing the Pasuk "b'Veged Tzemer O b'Veged Pishtim" by garments with which one merely covers oneself, and using "Tzemer u'Fishtim" to extend the Din to garments that one wears.

(c)We refute this suggestion however - because we would have already learned that from a 'Gezeirah-Shavah' (or a Giluy Milsa - a revelation) "Sha'atnez" "Sha'atnez" from Ha'ala'ah. That is why, according to Tana d'Bei Rebbi Yishmael, the Pasuk is Mufneh to teach us 'Aseh Docheh Lo Sa'aseh'.

6)

(a)Tana d'Bei Rebbi Yishmael hold the principle - that wherever the Torah uses the word "Begadim", it means either garments of wool or garments of linen.

(b)Based on the fact that "Shesh" (by the Bigdei Kehunah) is linen, we define "Techeles, Argaman and Tola'as Shani" mentioned there - as wool (since only wool and linen were used in the manufacture of the Bigdei Kehunah).

(c)This proves that a Beged of Tzitzis had to consist either of wool or linen ...

(d)... creating a problem with Tana d'Bei Rebbi Yishmael- who, if not for "Tzemer u'Fishtim", would forbid Kil'ayim b'Tzitzis (when the fact that a Beged of Tzitzis had to consist either of wool or linen and Techeles had to be wool seems to specifically permit it).

7)

(a)We initially answer that we need "Tzemer u'Fishtim" to preclude from Rava's Derashah of "ha'Kanaf". To answer the apparent contradiction between "ha'Kanaf" 'Min Kanaf' on the one hand, and "Tzemer u'Fishtim" on the other - Rava explains that Tzitzis of wool and linen exempt all garments, whereas Tzitzis made of other materials exempt only garments that are made of the same material as themselves.

(b)But Tana d'Bei Rebbi Yishmael disagrees with Rava. According to him, materials other than wool and linen are Patur from Tzitzis.

(c)In spite of the fact that the Torah is referring exclusively to wool and linen garments according to him - if not for "Tzemer u'Fishtim", he would have Darshened "ha'Kanaf" to mean that a woolen garment requires woolen Tzitzis, and a linen garment, linen Tzitzis. If that were so, the Din of Techeles would be confined to a woolen garment.

(d)Therefore the Torah writes "Tzemer u'Fishtim" to teach us that linen (white) Tzitzis are even permitted on a woolen garment, and woolen Tzitzis on a linen garment.