Genesis 15:9-13

9Then He said to him, “Bring Me a three year old young cow, a three year old she-goat, a three year old ram, a turtle-dove and a young bird.”

10So he brought all these to Him and cut them in half, and put each piece opposite the other; but he did not cut the birds.

11Then birds of prey came down upon the carcasses, but Abram drove them away.

12When the sun was about to set and a deep sleep fell on Abram, behold, terror of great darkness was falling upon him!

13Then He said to Abram, “Know for certain that your seed will be strangers in a land that is not theirs, and they will be enslaved and oppressed 400 years.