The wrath of God is not to be set in sharp contrast with the love and mercy of God. It is so often asserted that if God is truly love then he cannot be angry. But wrath and love are not mutually exclusive. In the NT as well as the Old, in Jesus as in the prophets and apostles the proclamation of God's mercy is accompanied by the preaching of his wrath. A holy God does not stand idly by when men act unrighteously, transgress the law, show disdain to him as their creator or spurn his love and mercy. He acts in a righteous manner punishing sin in the present and especially on the final day. Yet God also acquits the guilty, and only the person who understands something of the greatness of his wrath will be mastered by the greatness of his mercy. The converse is also true: only he who has experienced the greatness of God's mercy can understand something of how great that wrath must be.-- Peter T. O'Brien, Colossians, 185, quoting Stählin's TDNT entry on the wrath of God.