Genesis 15:4-8

4Now the word of the Lord came to him: “This one will not be your heir; instead, one who comes from your own body will be your heir.”

5He took him outside and said, “Look at the sky and count the stars, if you are able to count them.” Then he said to him, “Your offspring will be that numerous.”

6Abram believed the Lord, and he credited it to him as righteousness.

7He also said to him, “I am the Lord who brought you from Ur of the Chaldeans to give you this land to possess.”

8But he said, “Lord God, how can I know that I will possess it?”