Genesis 15:12-16

When the sun was going down, a deep sleep fell on Abram. Now terror and great darkness fell on him. He said to Abram, “Know for sure that your offspring will live as foreigners in a land that is not theirs, and will serve them. They will afflict them four hundred years. I will also judge that nation, whom they will serve. Afterward they will come out with great wealth; but you will go to your fathers in peace. You will be buried at a good old age. In the fourth generation they will come here again, for the iniquity of the Amorite is not yet full.”