Genesis 15:12-21

As the sun was going down, Abram fell into a deep sleep, and a terrifying darkness came down over him. Then the LORD said to Abram, “You can be sure that your descendants will be strangers in a foreign land, where they will be oppressed as slaves for 400 years. But I will punish the nation that enslaves them, and in the end they will come away with great wealth. (As for you, you will die in peace and be buried at a ripe old age.) After four generations your descendants will return here to this land, for the sins of the Amorites do not yet warrant their destruction.” After the sun went down and darkness fell, Abram saw a smoking firepot and a flaming torch pass between the halves of the carcasses. So the LORD made a covenant with Abram that day and said, “I have given this land to your descendants, all the way from the border of Egypt to the great Euphrates River— the land now occupied by the Kenites, Kenizzites, Kadmonites, Hittites, Perizzites, Rephaites, Amorites, Canaanites, Girgashites, and Jebusites.”