1)
Why does it say twice "va'Yelech"?
1.
Malbim: There was a revealed aspect of uprooting from his place to the Yarden, and a hidden aspect of causing Hashgachah to be uprooted to the border of Eretz Yisrael to stop rain. "Va'Yelech va'Ya'as ki'Dvar Hashem" refers to the latter; it made an impression Above according to Hashem's Dibur.