After articulating his gospel centering on a righteousness from God through justification by faith in Jesus Christ alone, Paul points us to Abraham as proof.
I. Abraham was a sinner like us, yet counted as righteous by God
II. Justification by faith saved Abraham from his past (the flesh).
III. Justification by faith secured Abraham’s future (his works can’t undo God’s declaration).
IV. So should it be for you, only believe God, and be justified.
27 Then what becomes of our boasting? It is excluded. By what kind of law? By a law of works? No, but by the law of faith. 28 For we hold that one is justified by faith apart from works of the law. 29 Or is God the God of Jews only? Is he not the God of Gentiles also? Yes, of Gentiles also, 30 since God is one—who will justify the circumcised by faith and the uncircumcised through faith. 31 Do we then overthrow the law by this faith? By no means! On the contrary, we uphold the law.
4 What then shall we say was gained by Abraham, our forefather according to the flesh? 2 For if Abraham was justified by works, he has something to boast about, but not before God. 3 For what does the Scripture say? “Abraham believed God, and it was counted to him as righteousness.”