Niebuhr didn't believe man was perfect before the fall that made us imperfect, that we went from complete perfection to complete imperfection, unlike what Holy Scripture teaches. Thus he proffered strongly that we can be moral in an immoral society, as if there could be such a disconnect. To give us a conscience, God's Word says that God wrote His Moral Law, the Ten Commandments, on everybody's heart. Without a conscience there is no possibility for morality. As each person collectively forms and composes society, one can only STRIVE for morality, but never succeed to be moral in immoral society. Niebuhr has Jacob Arminius to thank for his idea that man steeped in sin, as we all are, can be any kind of moral in an immoral society. The Bible tells us that our consciences both accuse and excuse our hearts, thus God tells us that His Law condemns us all as immoral sinners, but the Gospel gives us salvation, eternal life and forgiveness in Christ alone, presenting us sinners as perfect under the Gospel before our loving, living God.