There are really only 2 faiths in the world. Those that try to earn salvation by achieving righteousness through works, and Christianity, that believes that Jesus can gift us righteousness through faith in him.
The Jews believed the former. That salvation was by righteouesness through obedience to the Law. But Paul says that actually the Law and the Prophets speak about righteousness through faith, not the Law.
“But now a righteousness from God, apart from the law, has been made known, to which the Law and the Prophets testify” (Rom 3:21).
Wowsers. What a fiery verse to hear if you are Jewish. How is it possible? And where does it say that?
Paul goes on to say this has been so from the beginning, with Abraham. When God told Abraham that Sarah would give birth to a son, and that through him he would be the father of all who believe, father of nations, Abraham believed God. And the Scriptures say that this faith, this belief in the promises of God, was credited to Abraham as righteousness (Genesis 15:6).
Abram believed the Lord, and he credited it to him as righteousness (Genesis 15:6)
His righteousness was granted to him by God because of his faith. This happened before circumcision, and before the Law. His faith in God was what made him righteous.
Paul will go on to say the same was true with David.
David says the same thing when he speaks of the blessedness of the one to whom God credits righteousness apart from works:
7 “Blessed are those
whose transgressions are forgiven,
whose sins are covered.
8 Blessed is the one
whose sin the Lord will never count against them.” (Romans 4:7-8).
David had been busted for his affair with Bathsheba and his murder of her husband. The Lord was heavy upon his soul. David repented, and he found forgiveness through faith in God. Not through his actions.
This was a foreshadowing of faith in God who wipes away sins.
Paul returns to Abraham.
Abraham had faith in God, and that faith was counted as righteousness. He later was circumcised.
And he received circumcision as a sign, a seal of the righteousness that he had by faith while he was still uncircumcised (v. 11).
In this God was teaching that Abraham would be the father of everyone who has faith in God. That meant he was the father of the Gentiles who would believe even though they weren’t circumcised. And he would be the father of the Jews who would be circumcised, but also had faith.
Faith was essential in both.
Then why the Law?
Paul has just pointed out its purpose.
Therefore no one will be declared righteous in God’s sight by the works of the law; rather, through the law we become conscious of our sin (Romans 3:20).
The problem with the Law was that it couldn’t save. It was just the x-ray that showed the problem.
If we could be saved by the Law, then there is no need for faith. It all comes down to works. But Abraham’s righteousness was by faith, and not by works.
So where is our righteousness? For both Jews and Gentiles? In Galatians 3 he is going to spell it out that the “seed” of Abraham, the Messiah to come, was the placement of that faith.
But here in Romans he spells it out clearly:
23 The words “it was credited to him” were written not for him alone, 24 but also for us, to whom God will credit righteousness—for us who believe in him who raised Jesus our Lord from the dead. 25 He was delivered over to death for our sins and was raised to life for our justification.
Righteousness is by faith in the Messiah, Jesus Christ our Lord, who was promised by the Law and the Prophets, that would be a ransom for our sins. Through faith in Him, we are justified, and declared “not guilty” before God. Jesus gives us the gift of righteousness.
When we have faith and hope in Jesus, and do like Abraham who strengthened himself in that hope and faith, we have righteousness before God. Not of ourselves. But through Christ.