Genesis 15:4-6

Immediately, the word of YAHWEH came to him: “No! Eliezer will not be your heir. I will give you a son from your own body to be your heir.” Then YAHWEH brought him outside his tent and said, “Gaze into the night sky. Go ahead and try to count the stars.” He continued, “Your seed will be as numerous as the stars!” And Abram trusted every word YAHWEH had spoken! And because of his faith, YAHWEH credited it to him as righteousness.