Why does the Torah use the expression, "b'Etzem ha'Yom ha'Zeh"?
Rashbam, Riva; Hadar Zekenim (to 12:41): It is repeated here to teach us that the coming Parshah, "Kadesh Li Kol Bechor" (13:1-10) was said on the day that Yisrael left Egypt.
Why does the Torah repeat here what it already stated above (in 12:41)?
Ramban #1: To counter what it said in the next Pasuk, "Leil Shimurim Hu... l'Hotzi'am me'Eretz Mitzrayim" (12:42) -- which implies that the Exodus was at night, the Torah writes here that Hashem took them out to freedom by day; 1 "with all their hosts" - including men, women and the Eirev Rav. 2
Ramban #2 (citing the Ibn Ezra) and Rashbam: To teach us that on the day that Yisrael left Egypt, Hashem told Moshe the (following) Parshah of "Kadesh" (Shemos 13:1-16).
Moshav Zekenim (to 12:41): Above, the Torah discussed "Tziv'os Hashem" leaving, 3 whereas here it is discussing "Bnei Yisrael" leaving.
What are the implications of the words "Al Tziv'osam"?
Oznayim la'Torah: It implies that they left Egypt in an orderly fashion - like soldiers, numbered and by name - and not one soldier remained.
