Genesis 15:7-10

7And he said unto him, I am Yhwh that brought thee out of Ur of the Chaldees, to give thee this land to inherit it.

8And he said, Lord Yhwh, whereby shall I know that I shall inherit it?

9And he said unto him, Take me an heifer of three years old, and a she goat of three years old, and a ram of three years old, and a turtledove, and a young pigeon.

10And he took unto him all these, and divided them in the midst, and laid each piece one against another: but the birds divided he not.