Romans chapters 1-3 is a powerful reminder of our absolute and utter condemnation before the Holy God of the universe. If there was ever a question in any ones mind about "needing to be saved from what", these chapters paint the picture. To the pagan who denies the evidences of God in the universe and sets up idols to the religious person who judges others as a form of idolatry, we are all guilty under the law. But God through his grace on the basis of our faith chooses to justify us. This means that he makes us totally pure and right simply because we trust that he can. This then becomes "the law of faith" which creates in us an obedience from the heart in serving the living God.