What is the definition of "Bein ha'Arbayim," and why is it called by that name?
Rashi: Refer to Shemos 12:6:5:1.
Ramban: Refer to Shemos 12:6:5:2.
Since when is Pesach on the 14th of Nisan?
Rashi: Pesach in this Pasuk refers (not to the Yom-Tov, but) to the bringing of the Korban by the same name.
Since the fourteenth of Nisan is not included in the Mikra'ei Kodesh, why does the Torah insert it here?
Seforno: Because it is the cause of the fixture of the Yamim-Tovim, 1 since, on account of the first Korban Pesach that was brought in Egypt, Pesach must always be arranged to fall in the spring - like it did then. 2
Oznayim la'Torah: In fact, it is the main reason for fixing a leap-year - as the Torah writes in Re'eh (Devarim 10:1), "Shamor Es Chodesh ha'Aviv." See Oznayim la'Torah.
Seforno: As the Torah indicates in Devarim 16:1.
Why does the Torah write "Pesach La'Shem"?
Moshav Zekenim, citing R. Eliezer of Garmaiza: It is a time when Hashem has mercy on His creations, from the Creation until now. Refer to Shemos 12:11:4:2.
Moshav Zekenim #1: Read "Pesach" as 'Peh Sach' - [Avraham's] mouth, which said "ba'Mah Eda" (Bereishis 15:8), caused His children to be enslaved until this time.
Moshav Zekenim #2: "Pesach" is the acronym of 'Peh Sach', as if to say 'The mouth on the Merkavah (Hashem's chariot) speaks' - It announces that the time to redeem Yisrael has arrived. In other words, the letters on the Merkavah advocate for Yisrael.
