Genesis 15:1-6

After these things the word of the LORD came to Abram in a vision: “Fear not, Abram! I am your shield and the one who will reward you in great abundance.” But Abram said, “O sovereign LORD, what will you give me since I continue to be childless, and my heir is Eliezer of Damascus?” Abram added, “Since you have not given me a descendant, then look, one born in my house will be my heir!” But look, the word of the LORD came to him: “This man will not be your heir, but instead a son who comes from your own body will be your heir.” The LORD took him outside and said, “Gaze into the sky and count the stars – if you are able to count them!” Then he said to him, “So will your descendants be.” Abram believed the LORD, and the LORD considered his response of faith as proof of genuine loyalty.