1)

(a)The time for the Mitzvah of Bi'ur Chametz cannot be the night of the fourteenth - because the Torah writes "Ach ba'*Yom* ha'Rishon".

(b)Nor does it fall due already in the morning - since "Ach" teaches us to divide the day, half is permitted, and half is forbidden.

(c)Tana d'Bei Rebbi learns from the Pasuk "ba'Rishon b'Arba'ah-Asar Yom la'Chodesh" - that sometimes, the Torah refers to the fourteenth as 'Rishon'.

2)

(a)Rav Nachman bar Yitzchak learns from "ha'Rishon Adam Tivaled" - that sometimes "Rishon" means 'before' rather than 'first'.

(b)"u'Lekachtem Lachem ba'Yom ha'Rishon" cannot mean the day before - because the Torah also writes "u'Semachtem Lifnei Hash-m Elokechem Shiv'as Yamim"; just as the 'seventh day' means the seventh day of Yom-Tov, in the same way, the 'first day' must mean the first day of Yom-Tov.

(c)The Gemara objects to the contention that 'Rishon' should mean the 'day before' from the extra 'Hey' of 'ha'Rishon' - because in that case, we should also obligate taking the Lulav the day before Succos, since there too, the Torah writes ba'Yom ha'Rishon.

(d)The Gemara objects to learning the 'Hey' of ha'Rishon by the Yom-Tov of Succos to preclude Chol ha'Mo'ed from the Din of Mikra Kodesh - because we know that already from 'Rishon' and 'Shemini'.

3)

(a)Rav Nachman bar Yitzchak accounts for the extra 'Hey' in 'ha'Rishon by ...

1. ... the Mikra Kodesh of Pesach - to hint at the merit of the destruction of Eisav (the Se'or she'be'Isah), by which the Pasuk in Toldos writes "Veyetzei ha'Rishon Admoni".

2. ... the Mikra Kodesh of Succos - to hint to the construction of the Beis Hamikdash, by which the Navi Yirmayah writes "Kisei Kavod Marom me'Rishon".

3. ... the Mitzvah of Lulav - to hint at the merit of the coming of Mashi'ach, by which the Navi Yeshayah writes "Rishon l'Tziyon Hinei Hinam". (See Agadas Maharsha)

4)

(a)"Lo Sishchat Al Chametz Dam Zivchi" - teaches us that one is not permitted to Shecht the Korban Pesach (i.e. from mid-day, when the Mitzvah falls due), and have Chametz in one's possession.

(b)The Torah is not giving each person his own personal time to destroy his Chametz, but a time when everyone must do so ('Nasata Devarecha l'Shiurin').

5)

(a)Rebbi Akiva learns it from "Ach ba'Yom ha'Rishon Tashbisu ... Kol Melachah Lo Sa'asu" - if "ba'Yom ha'Rishon" would mean literally the first day of Yom-Tov, how would it be permitted to burn the Chametz on Yom-Tov? It is only permitted to make a fire and to cook, if it is for Ochel Nefesh, but not for a Mitzvah per se (see Tosfos DH 'Kol Melachah Lo Sa'asu').

(b)Rava learns from Rebbi Akiva's opinion - that 1. 'Ein Bi'ur Chametz Ela Sereifah' (like his Talmid, Rebbi Yehudah); 2. Hav'arah (making a fire) is an Av Melachah like Rebbi Nasan, who learns that the Torah mentions Hav'arah in order to be Mechayav for each Melachah individually (not to single out Hav'arah, to teach us that it is only a La'av and not Kares - like Rebbi Yosi); 3. That we do not say 'Ho'il v'Hutrah Hav'arah l'Tzorech, Hutrah Nami she'Lo l'Tzorech'.

(c)Rebbi Yosi Hagelili learns from "Ach ba'Yom ha'Rishon Tashbisu". This cannot be referring to the fifteenth, because "Ach" permits retaining the Chametz for part of the day - and, as we learnt above, the Torah compares the Mitzvah of destroying Chametz to the prohibition of eating it, and the prohibition of eating it to the Mitzvah of eating it. This in turn means, that one may not have any Chametz on the night of the fifteenth. Consequently, "ba'Yom ha'Rishon" can only mean on the fourteenth.

6)

(a)We learn from the Pasuk ...

1. ..."Lo Yera'eh Lecha Se'or b'Chol Gevulecha" - that it is only your own Chametz (which belongs to a Jew) that is forbidden, but not Chametz which belongs to a non-Jew or to Hekdesh.

2. ... "Lo Yimatzei" - 1. that neither is hiding the Chametz permitted and 2. nor may one receive Chametz from gentiles to look after (since here, the Torah does not write "Lecha").

(b)And the Torah adds "Shiv'as Yamim Se'or Lo Yimatzei b'Vatechem" - to include even the Chametz of a non-Jew who is under your jurisdiction and who lives in the same Chatzer as you (we shall see later what this means).

(c)We learn from the first "b'Chol Gevulecha" - that the Isur of Chametz is not confined to houses, but extends even to Chametz in pits, trenches and caves.

(d)We know that Bal Yera'eh and Bal Yimatzei, Bal Yatmin and Bal Yekabel Pikdonos min ha'Nochri apply even by Gevulim; and that 'she'Lecha I Ata Ro'eh, Aval Ata Ro'eh shel Acherim' applies even to houses - because of the Gezeirah Shavah "Se'or" "Se'or", one written by Batim and the other, by Gevulim.

7)

(a)If the Chametz of a non-Jew who is not under your jurisdiction (or who do not live with you in the same courtyard) is forbidden, then why should we need another Pasuk to include one who is? Is that not obvious!?

(b)Rava establishes that part of the Beraisa, not by the Seifa, which deals with the La'av of Lo Yimatzei, but by the Reisha, with regard to the Heter of 'Lecha' (permitting the Chametz of gentiles).

(c)The Pasuk "Lo Yera'eh Lecha Se'or" appears twice, once in Re'ei and once in Bo. The latter is redundant, so we use it for the Pasuk of "Lo Yimatzei", as if the Torah had written "Lo Yimatzei Lecha" (Even what is Matzuy i.e. when the non-Jew is Matzuy by you); it is permitted, because it is not yours. And it is in that context that the Gemara quotes the Pasuk "Lo Yimatzei b'Vateichem" (in itself, a Pasuk that comes to be stringent).

8)

(a)The Reisha, which forbids the accepting of a security of Chametz from a gentile - speaks in a case when the Jew accepted responsibility should something happen to the Chametz (then it is as if he was the owner); whereas the Seifa, which permits it, speaks when he did not. Note: See Rosh Si'man 4, as to whether the responsibility needs to be that of a Shomer Sachar to be forbidden, or whether even just that of a Shomer Chinam will suffice.

(b)Rava told the inhabitants of Mechoza - to burn the Chametz which the non-Jewish soldiers had deposited with them, because, since they had accepted responsibility should it become stolen or lost, it was as if the Chametz was theirs.

(c)According to those who hold 'Davar ha'Gorem l'Mamon, La'av k'Mamon Dami' - how can the Chametz be considered theirs!?

(d)Even if 'Davar ha'Gorem l'Mamon, La'av k'Mamon Dami' - answers the Gemara, the Chametz is nevertheless considered theirs, because the Torah writes "Lo Yimatzei", and once they accepted responsibility, it is considered Matzuy.

9)

(a)In the second Lashon, the Gemara asks that, according to Rebbi Shimon, who holds 'Davar ha'Gorem l'Mamon, k'Mamon Dami', why do we need "Lo Yimatzei"?

(b)Rebbi Shimon, answers the Gemara, speaks when the article in question is stolen or lost, and that is why it is considered Mamon; whereas here, we are speaking when the Chametz is still there, in which case, he can return it to the owner. Consequently, even according to Rebbi Shimon it would not be considered his - if not for the Pasuk "Lo Yimatzei".