Genesis 15:13

13Then the  Lord said to Abram, “Know for certain a  that your offspring will be sojourners in a land that is not theirs and will be servants there, and b  they will be afflicted for c  four hundred years.

Genesis 15:16

16And they shall come back here in the fourth generation, for d  the iniquity of the Amorites e  is not yet complete.”

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