Genesis 15:13-16

13 And he said to Abram, Know of a surety that your seed shall be a stranger in a land that is not their's, and shall serve them; and they shall afflict them four hundred years;

14 And also that nation, whom they shall serve, will I judge: and afterward shall they come out with great substance.

15 And you shall go to your fathers in peace; you shall be buried in a good old age.

16 But in the fourth generation they shall come here again: for the iniquity of the Amorites is not yet full.