Genesis 15:16-18

After your great-great-grandchildren are born, your people will come to this land again. It will take that long, because I am not yet going to punish the Amorites for their evil behavior.” After the sun went down, it was very dark. Suddenly a smoking firepot and a blazing torch passed between the halves of the dead animals. So on that day the LORD made an agreement with Abram and said, “I will give to your descendants the land between the river of Egypt and the great river Euphrates.