Romans 4:1-5;
What then are we to say was gained by Abraham, our ancestor according to the flesh? For if Abraham was justified by works, he has something to boast about, but not before God. For what does the scripture say? “Abraham believed God, and it was reckoned to him as righteousness.” Now to one who works, wages are not reckoned as a gift but as something due. But to one who does not work but trusts him who justifies the ungodly, such faith is reckoned as righteousness. So also David pronounces a blessing on those to whom God reckons righteousness apart from works:

“Blessed are those whose iniquities are forgiven and whose sins are covered; blessed is the one against whom the Lord will not reckon sin.”

Is this blessing, then, pronounced only on the circumcised or also on the uncircumcised? We say, “Faith was reckoned to Abraham as righteousness.” How then was it reckoned to him? Was it before or after he had been circumcised? It was not after but before he was circumcised. He received the sign of circumcision as a seal of the righteousness that he had by faith while he was still uncircumcised.

James 2:21-24
Was not our ancestor Abraham justified by works when he offered his son Isaac on the altar? You see that faith was active along with his works, and by works faith was brought to completion. Thus the scripture was fulfilled that says, “Abraham believed God, and it was reckoned to him as righteousness,” and he was called the friend of God. You see that a person is justified by works and not by faith alone.