" Romans 4 is all about the covenant that God made with Abraham in Genesis 15. It is not a detached statement about someone in the ancient scriptures who was “justified by faith.” It is not simply a “proof from scripture” of the “doctrine” that Paul has stated in Romans 3. Abraham is not simply an “example” of either the way God’s grace operates or the way some humans have faith. "
― N.T. Wright , The Day the Revolution Began: Reconsidering the Meaning of Jesus's Crucifixion