Genesis 15:8 (KJV)

And Abram said, Behold, to me thou hast given no seed: and, lo, one born in my house is mine heir.

And, behold, the word of the LORD came unto him, saying, This shall not be thine heir; but he that shall come forth out of thine own bowels shall be thine heir.

And he brought him forth abroad, and said, Look now toward heaven, and tell the stars, if thou be able to number them: and he said unto him, So shall thy seed be.

And he believed in the LORD; and he counted it to him for righteousness.

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

And 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.

And 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.

And when the fowls came down upon the carcases, Abram drove them away.

And when the sun was going down, a deep sleep fell upon Abram; and, lo, an horror of great darkness fell upon him.

And he said unto Abram, Know of a surety that thy 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;