Jamieson, Fausset and Brown on Genesis 46:2

2. God spake unto Israel--Here is a virtual renewal of the covenant and an assurance of its blessings. Moreover, here is an answer on the chief subject of Jacob's prayer and a removal of any doubt as to the course he was meditating. At first the prospect of paying a personal visit to Joseph had been viewed with unmingled joy. But, on calmer consideration, many difficulties appeared to lie in the way. He may have remembered the prophecy to Abraham that his posterity was to be afflicted in Egypt and also that his father had been expressly told not to go [Ge 15:13; 26:2]; he may have feared the contamination of idolatry to his family and their forgetfulness of the land of promise. These doubts were removed by the answer of the oracle, and an assurance given him of great and increasing prosperity.