After these things the word of the Lord came to Abram in a vision, "Do not be afraid, Abram, I am your shield; your reward shall be very great."
But Abram said, "O Lord God, what will you give me, for I continue childless, and the heir of my house is Eliezer of Damascus?"
References for Genesis 15:2
And Abram said, "You have given me no offspring, and so a slave born in my house is to be my heir."
But the word of the Lord came to him, "This man shall not be your heir; no one but your very own issue shall be your heir."
He brought him outside and said, "Look toward heaven and count the stars, if you are able to count them." Then he said to him, "So shall your descendants be."
And he believed the Lord; and the Lord reckoned it to him as righteousness.
References for Genesis 15:6