Genesis 15:13; Genesis 15:16; Genesis 15:18

13 Then the LORD said to Abram, "Know of a surety that your descendants will be sojourners in a land that is not theirs, and will be slaves there, and they will be oppressed for four hundred years;
16 And they shall come back here in the fourth generation; for the iniquity of the Amorites is not yet complete."
18 On that day the LORD made a covenant with Abram, saying, "To your descendants I give this land, from the river of Egypt to the great river, the river Euphra'tes,