Brothers and sisters in Christ:
I think St. Paul, in Eph 2:8,9, contrasts salvation by grace and salvation by works–and not salvation by faith and salvation by works.
He is saying salvation comes from grace, which is a gift of God–not a reward, not for something we did. If salvation can be had by works and not by God’s grace, we would boast about it so much we could say “God had nothing to do with it. We did it all alone–without his help.”
But salvation is not had by works but by grace. Anyone who believes he is saved by works and not by grace is in error. Salvation by works is a false teaching, a heresy called Pelagianism.
As for Gal 2:16-21, I see the same point St. Paul made in the previous passage in this passage. Once again, he contrast salvation by grace and salvation by works. Note the opening: “. . .(yet) who know that a person is not justified by works of the law but through faith in Jesus Christ. . .” and compare it with the opening in the previous passage “. . .For by grace you have been saved through faith. . .”
Why are we justified through faith in Jesus Christ? Grace, “. . .the gift of God. . .”;that’s why! By believing in Christ, we receive His grace, which justifies and saves us! Even our believing in Christ, our faith in Him is a grace! If anyone thinks that works justifies, that works saves–and not grace–then what is grace for? If we don’t need grace, then what is believing in Christ for? If we don’t believe in Christ, then He “. . .died for nothing.” Clearly, we would be in error if we think like this.
However, what is this “faith” St. Paul referring to. St. James describes this “faith” in Jm 2:14-26. He says true faith is not without works because “. . .just as a body without a spirit is dead, so also faith without works is dead” and “. . .a person is justified by works and not by faith alone. . .” And true faith, I repeat, is a grace–". . .the gift of God. . ."
I just realized something. The good thief on the cross, he did not only believe (although believing can be considered a work) but also did a good work. What did he do? In Lk 23:40-41, he, “. . .rebuking him, said in reply, ‘Have you no fear of God, for you are subject to the same condemnation? And indeed, we have been condemned justly, for the sentence we received corresponds to our crimes, but this man has done nothing criminal.’”. The good thief rebuked the other one for demanding to be spared from a just punishment for his sins; is this not admonishing the sinner–the bad thief? By speaking out that our Lord “. . .has done nothing criminal. . .” and thus implying that He should not have received any sentence at all; is this not admonishing the sinners–the Jews, the Romans and all men and women of all times? Is not admonishing the sinner a work of mercy, a spiritual work of mercy?
Shalom, amen.