Since Yaakov already made a Neder to sacrifice to Hashem in Beis El (28:20-22), why did Hashem see fit to instruct him to do it?
Rashi: This was a warning to stop dilly-dallying 1 and to go immediately to Beis El in order to fulfill his Neder, 2 because it was due to his delaying the issue until now that the incident with Dinah had occurred. 3
Oznayim la'Torah: Since Yaakov and his children were in grave danger, Hashem turned his journey to Beis El into a Shelichus of Mitzvah, to protect him against the enemies who would otherwise have attacked him. 4
Gur Aryeh: Why explain this way? The command "Get up!" is extra. It implies, 'Why are you still sitting here, and thus delaying the fulfillment of your vow?!'
Hadar Zekenim citing a Midrash: Also Elifaz took his money, the angel harmed him and Rachel died due to delaying to fulfill his vow (perhaps the Torah is out of order, and Hashem said this after she died).
Oznayim la'Torah: As the Gemara says in Pesachim 8a, 'Sheluchei Mitzvah Einan Nizokin.'
Seeing as Yaakov did not remain in Beis El, what did Hashem mean when He said to Yaakov, "v'Shev Sham"?
Ramban #1: He meant that Yaakov should cleanse himself from the Avodah-Zarah (of Shechem), or from the Tum'as Mes 1 of the people he had slain, during a waiting period at Beis El before building any Mizbe'ach.
Ramban #2 and Seforno: He meant that Yaakov should clear his mind of other thoughts, in order to cling fully to Hashem. 2
Oznayim la'Torah #1: He meant that Yaakov should pray there. 3
Oznayim la'Torah #2 (to 35:16): Hashem only meant that Yaakov should remain there until he had fulfilled his Neder.
Ohr ha'Chayim #1: Even though it is part of Eretz ha'Kena'ani, dwell there and do not fear them.
Ohr ha'Chayim #2: Dwell there, and not here, for damage is common in the place of the breach (killing the entire city)
Ohr ha'Chayim #3: Hashem hinted that he should have dwelled there, and not here. He should not have rested until going to build the Mizbe'ach, like he vowed.
Ha'amek Davar: Before you fulfill the vow, pray for the present. Do not rush to erect the Matzevah; first build a Mizbe'ach, which is better for Tefilah. A Matzevah is better for thanks, or to get Ru'ach ha'Kodesh. After Yaakov arrived, he built a Mizbe'ach, but did not erect a Matzevah until after Devorah and Rivkah died, the period of crying passed, and Hashem spoke to him there! 4
See Bamidbar 31:19 (Ramban).
Seforno: As the Gemara says in Berachos (30b) regarding the early Chasidim.
Oznayim la'Torah: Like we find in Shemos 24:14 - according to the Yalkut Shim'oni.
Ha'amek Davar: We learn from here that if one was obligated to bring a Todah or bless ha'Gomel, and another affliction came, he brings the Todah or blesses only after he is saved from the latter affliction.
What was the purpose of the Mizbe'ach?
Ramban and Seforno: To fulfill the Neder that he had made on his way to Charan, 22 years earlier. 1
Seforno: It can also be compared to what the Gemara says (Berachos 54a) regarding the Berachah, 'Baruch she'Asah Li Nes ba'Makom ha'Zeh.'
QUESTIONS ON RASHI
Rashi writes that the episode with Dinah was due to delaying his vow. Above, he said that it was because he locked her in a box to withhold her from Esav (refer to 32:23:1:1)!
Bartenura: The episode with Dinah was due to both of these.
Mizrachi: Delaying the vow was due to the Aveirah of withholding her from Esav. To do so, he needed to delay in Sukos. 1 Do not say that Rashi cites Midrashim that argue with each other. Bereishis Rabah (76:9) says that it was due to Shechem, and in 81:2, it says that one who delays his vow, his ledger is opened (to see if he should be punished)!
Gur Aryeh: Because he withheld her from the (erstwhile) wicked Esav, she fell to the wicked Shechem - measure for measure. However, this decree might have been undone though prayer or repentance. When a person delays fulfillment of a vow, his 'ledger is opened' - i.e. his accounts are reviewed [by Heaven - and retribution came immediately]. 2
Divrei David: Had he not delayed, he could not have been punished on the way, for he was a Shali'ach Mitzvah. Hashem had commanded him, "Shuv El Eretz Avosecha" (31:3).
He does not explain why he needed to delay in Sukos in order to withhold her from Esav. Chizkuni and Riva say similarly, but it seems that there is a printing mistake. They say that withholding her also caused him to delay in Shechem and Beis El. He came to Beis El after the episode with Dinah, and he needed to go there to fulfill his vow! (PF)
Gur Aryeh: See Yerushalmi (Nedarim 1:1), based on Mishlei 20:25.
