Yet he did not waver through unbelief regarding the promise of God, but was strengthened in his faith and gave glory to God, 21 being fully persuaded that God had power to do what he had promised.
Justification by Faith
Paul goes back not to the OT to show that the faith principle has always operated in the same way. Abraham’s faith was credited to him for righteousness, according to Genesis 15:6. And in Psalm 32:1, 2 David speaks of the same truth.
As for circumcision, Abraham was justified by faith faith before the rite was given. Thus Abraham’s justification by faith sets the pattern for both Jews and Gentiles. Paul goes on to show that God’s covenant promise was received by faith and thus is not related to law either.
It is clear then from this analysis that justification by faith is boldly affirmed in the OT! So Paul goes on to analyze the nature of faith. When God’s promise of an offspring was made to Abraham he was nearly a hundred years old and his wife Sarah ninety.
Abraham faced these facts. But he also took into account the fact of God!
18 Against all hope, Abraham in hope believed and so became the father of many nations, just as it had been said to him, “So shall your offspring be.” 19 Without weakening in his faith, he faced the fact that his body was as good as dead—since he was about a hundred years old—and that Sarah’s womb was also dead. 20 Yet he did not waver through unbelief regarding the promise of God, but was strengthened in his faith and gave glory to God, 21 being fully persuaded that God had power to do what he had promised.
… 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.
Justification is a courtroom language. What then is “justification”? It is a judicial act of God by which he declares us righteous. To understand this great theological term, we must imagine an individual standing before God the judge, his life and character and every activity under examination.
Paul tells us in Romans that, if a human being were to “do good” and keep either the law of conscience or Moses, God would declare him righteous (Romans 2:12-6). But Paul shows us that all have sinned and fallen short. How then can God the judge declare a verdict of “not guilty” over any man?
Paul goes on to explain that God has already announced a stunning verdict! We “are justified freely by his grace, through the redemption that came by Christ Jesus” (Rom. 3:24). God has accepted the blood of Christ as an atoning sacrifice for our sins and because of Jesus has declared man justified (3:25, 26).
In an objective sense Christ died for all, and the verdict of “not guilty” has been pronounced over all humanity. In a personal sense, each individual must accept the announced pardon. This pardon, the Bible says, is forgiveness in Jesus.