Genesis 15:7-11

And He said to him, “I am the Lord who brought you out of Ur of the Chaldeans, to give you this land to possess it.”

But he said, “Lord God, how may I know that I will possess it?”

So He said to him, “Bring Me a three-year-old heifer, a three-year-old female goat, a three-year-old ram, a turtledove, and a young pigeon.”

Then he brought all these to Him and cut them in two, and laid each half opposite the other; but he did not cut the birds.

And birds of prey came down upon the carcasses, and Abram drove them away.