Genesis Chapter 15

15:5
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.

15:12
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 theirs, and shall serve them; and they shall afflict them four hundred years;
And also that nation, whom they shall serve, will I judge: and afterward shall they come out with great substance.
And thou shalt go to thy fathers in peace; thou shalt be buried in a good old age.
But in the fourth generation they shall come hither again: for the iniquity of the Amorites is not yet full.
And it came to pass, that, when the sun went down, and it was dark, behold a smoking furnace, and a burning lamp that passed between those pieces.