The glory of the gospel is that God has declared Christians to be rightly related to him in spite of their sin. But our greatest temptation and mistake is to try to smuggle character into his work of grace. How easily we fall into the trap of assuming that we remain justified only so long as there are grounds in our character for that justification. But Paul’s teaching is that nothing we do ever contributes to our justification. So powerful was his emphasis on this that men accused him of teaching that it did not matter how they lived if God justified them. If God justifies us as we are, what is the point of holiness? There is still a sense in which this is a test of whether we offer the world the grace of God in the gospel. Does it make men say: ‘You are offering grace that is so free it doesn’t make any difference how you life’? This was precisely the objection the Pharisees had to Jesus’ teaching!
-Sinclair B. Ferguson