But to him who does not work but believes on Him who justifies the ungodly, his faith is accounted for righteousness, 6. just as David also describes the blessedness of the man to whom God imputes righteousness apart from works: 7. “Blessed are those whose lawless deeds are forgiven, and whose sins are covered;8. blessed is the man to whom the Lord shall not impute sin.” (Romans 4.5-8)
In Romans 3:21 and following, on into chapter 4 the Apostle Paul is contrasting faith and works. He is saying over and over that salvation comes by believing in what God has done, not by our doing. And then he makes this point in Romans 4:5-8 that is crucial to understand salvation.
In order for someone to be acceptable to God, they must be two things. They must be perfectly sinless and perfectly righteous. I hope we can see the problem immediately. God’s standards are impossible for any of us to meet. Who among us is perfectly sinless and perfectly righteous? Or who among us could, by working, ever make themself perfectly sinless or perfectly righteous? If you are sinful, (which we all are- see Romans 3) no amount of working or doing can make you ‘unsinful’. If you are unrighteous, no amount of working or doing can make you perfectly righteous.
But in Romans 4 Paul is saying that by believing in Jesus Christ’s work on our behalf, God will put Jesus’ perfect righteousness to our account, and God will put our sinfulness to Jesus’ account. So the perfect righteousness we need becomes ours through imputation, and the perfect sinlessness we need becomes ours through imputation as well!
So, as we consider these truths hopefully it becomes more evident to us that salvation is, and must be something that can only come about through believing. We must come to know that we are sinners who need a Savior, a Savior who made all provision for us to be accepted with the Father, accepted into His eternal presence. We must come to believe the Gospel!
17. Therefore, if anyone is in Christ, he is a new creation; old things have passed away; behold, all things have become new. 18. Now all things are of God, who has reconciled us to Himself through Jesus Christ, and has given us the ministry of reconciliation, 19. that is, that God was in Christ reconciling the world to Himself, not imputing their trespasses to them, and has committed to us the word of reconciliation. 20. Therefore we are ambassadors for Christ, as though God were pleading through us: we implore you on Christ’s behalf, be reconciled to God. 21. For He made Him who knew no sin to be sin for us, that we might become the righteousness of God in Him. (2 Corinthians 5.17-21)