Now there was a famine in the land, besides the former famine that was in the days of Abraham. The author distinguishes this famine from the previous one that had brought Abraham to Egypt. And the Lord appeared to him and said, “Do not go down to Egypt; As Abraham did. What trouble came out of Egypt for him? See Genesis 13 and 16.  Egypt was a land of false gods,  and continually a place of trial and hardship for God’s people.  Isaac was not permitted to go by the Lord, though Abraham was. This was a protective order.   Sojourn in this land, and I will be with you and will bless you, for to you and to your offspring I will give all these lands, and I will establish the oath that I swore to Abraham your father.  God confirms his promise.  because Abraham obeyed my voice and kept my charge, my commandments, my statutes, and my laws.  As Isaac should, as we all should, that God will keep and bless us.  For our inadequacy in following God, He sent us Christ.