Genesis 15:1-6

Later the LORD spoke to Abram in a vision, “Abram, don't be afraid! I will protect you and reward you greatly.” But Abram answered, “LORD All-Powerful, you have given me everything I could ask for, except children. And when I die, Eliezer of Damascus will get all I own. You have not given me any children, and this servant of mine will inherit everything.” The LORD replied, “No, he won't! You will have a son of your own, and everything you have will be his.” Then the LORD took Abram outside and said, “Look at the sky and see if you can count the stars. That's how many descendants you will have.” Abram believed the LORD, so the LORD was pleased with him and accepted him.