Romans 4:16-17

And so the promise was based on faith, in order that the promise should be guaranteed as God's free gift to all of Abraham's descendants — not just to those who obey the Law, but also to those who believe as Abraham did. For Abraham is the spiritual father of us all; as the scripture says, “I have made you father of many nations.” So the promise is good in the sight of God, in whom Abraham believed — the God who brings the dead to life and whose command brings into being what did not exist.