Romans 4:16-18

16For this reason it is by faith so that it may be by grace, with the result that the promise may be certain to all the descendants – not only to those who are under the law, but also to those who have the faith of Abraham, who is the father of us all

17(as it is written, “I have made you the father of many nations”). He is our father in the presence of God whom he believed – the God who makes the dead alive and summons the things that do not yet exist as though they already do.

18Against hope Abraham believed in hope with the result that he became the father of many nations according to the pronouncement, “so will your descendants be.”