Genesis 15:15-18

As for you, you shall go to your fathers in peace; you shall be buried in a good old age. And they shall come back here in the fourth generation, for the iniquity of the Amorites is not yet complete.” When the sun had gone down and it was dark, behold, a smoking fire pot and a flaming torch passed between these pieces. On that day the LORD made a covenant with Abram, saying, “To your offspring I give this land, from the river of Egypt to the great river, the river Euphrates