What is the significance of the fact that the Torah inserts "u'Vanav," before it begins the list of Yaakov's grandchildren?
Seforno: It was only Yaakov and his sons who were personalities great enough for their names to be famous and on the Choshen, 1 but not his grandchildren, even though also they were Tzadikim.
See also the opening Rashi in Sefer Shemos.
Why does the Torah write "ha'Ba'im" (in the present), and not 'she'Ba'u' (in the past)?
Rashi: The Torah is speaking from the perspective of the time that the event occurred, as if they were just arriving in Egypt. 1
Gur Aryeh (citing Mizrachi): From the perspective of Moshe at the time that he transcribed the Torah, these events had occurred in the past! (Indeed, the narratives in the Torah are usually in past tense). Here, the Torah uses a perspective as if present at that time.
Why does the Torah not count Yaakov in the list of those who came down to Egypt?
Rashbam, (Ibn Ezra to 46:23), Da'as Zekenim, Hadar Zekenim: Indeed, Yaakov was the seventieth soul. 1
Ohr ha'Chayim: Sometimes he is counted, and sometimes not. Here it says "Yaakov u'Vanav," to teach that he is counted with Bnei Leah. Verse 46:15 says "Kol Nefesh Banav u'Venosav" to teach that the count of 33 includes him and his children; perhaps we expound "Kol." It does not say Kol regarding Bnei Zilpah (46:18). It says Kol regarding Bnei Bilhah (46:25) because there were only seven. Also, 'Leidah' is mentioned regarding Zilpah, Rachel and Bilhah, but not regarding Leah, for one of the 33 attributed to her (Yaakov), she did not give birth to him.
Maharal (Gevuros Hashem Ch. 13, p. 68): Yaakov was the root [of Am Yisrael]; it was his offshoots (i.e. descendants) that were counted. Counting is not relevant to a single unit.
Rashbam: This is the simple explanation; but Chazal explained that Yocheved was the seventieth. Refer to 46:15:2:1. (In other contexts as well, the primary opinion does not count the head among the 70. A) The 70 nations, or languages, correspond to these 70 (Rashi to Devarim 32:8, from Bamidbar Rabah 9:14). Most explain that Yisrael is not among the 70 nations; Tosfos Shantz (to Sotah 36b) was unsure. B) The Great Sanhedrin also corresponds to the 70 nations (Midrash Sechel Tov Shemos 1:5, Moshav Zekenim to Bamidbar 11:16). R. Yehudah holds that there are 70 judges in all; Chachamim hold that Moshe is the 71st (Sanhedrin 16b) - PF.)
