Adam Clarke on Genesis 46:1

And came to Beer-sheba - This place appears to be mentioned, not only because it was the way from Hebron, where Jacob resided, to Egypt, whither he was going, but because it was a consecrated place, a place where God had appeared to Abraham, Gen 21:33, and to Isaac, Gen 26:23, and where Jacob is encouraged to expect a manifestation of the same goodness: he chooses therefore to begin his journey with a visit to God's house; and as he was going into a strange land, he feels it right to renew his covenant with God by sacrifice. There is an old proverb which applies strongly to this case: "Prayers and provender never hinder any man's journey. He who would travel safely must take God with him.