Why did Hashem repeat Yaakov's name twice?
Rashi: This is a sign of love. 1
Refer to 6:9:151:1; refer to Shemos 3:4:151:1.
Having changed his name to Yisrael, why did Hashem address him as Yaakov?
Ramban: Because he was now on his way down to Galus, where he was not destined to rule over his enemies. 1
Moshav Zekenim: Hashem said that others will not call him Yaakov, but Hashem himself may. Others called him Yaakov due to trickery, but Hashem called him so due to holding the ankle [at birth].
Ha'amek Davar: 'Yisrael' implies a high level that pertains to especially to the nation, which comes only via Torah and Avodah, and is distanced from the ways of all other people. 'Yaakov' is in a simple aspect of people whose good deeds correspond to the ways of the world. Here Hashem told him to leave Eretz Yisrael to go to Egypt, where he will remain at a simpler level.
The name Yisrael is based on being on top. Ha'amek Davar questions this, for we find the name Yisrael during the Galus!
Since Hashem called him "Yaakov," why is he called Yisrael elsewhere in this Parshah?
Ramban: Because in Egypt his children will grow greatly in number and in esteem.
Seforno: It was a message that his children would eventually be required to rule over their enemies in Kena'an. 1
Why does it say "b'Mar'os ha'Laylah"?
Ha'amek Davar: Hashem appeared to Yaakov during the day, with visions of the night, to help him understand that the time came to accept the yoke of exile, which is called night. The world is dark then from (i.e. it lacks) Ru'ach ha'Kodesh, except for brief times for a need, like a lightning bolt that illuminates the night.
