Genesis 15:13-16

13Then the Lord said to Abram, “Know for certain that your descendants will be strangers in a foreign country. They will be enslaved and oppressed for four hundred years.

14But I will execute judgment on the nation that they will serve. Afterward they will come out with many possessions.

15But as for you, you will go to your ancestors in peace and be buried at a good old age.

16In the fourth generation your descendants will return here, for the sin of the Amorites has not yet reached its limit.”