"With my mouth I will greatly extol the LORD; in the great throng of worshippers I will praise him." (Psalm 109:30)
Psalm 109 is the most intense of the imprecatory psalms, a prayer of one who has been deeply wronged and who calls down specific judgments on his tormentors. The accusers have repaid good with evil and love with hatred, and the psalmist responds with a cascade of curses. This psalm is one of the most difficult in the Christian tradition, and the Church has never pretended otherwise.
Several interpretive approaches have been offered by the tradition. St. Augustine read the curses not as the psalmist's own prayer but as a description of what the enemies have brought upon themselves by their own wickedness: these judgments are the natural consequence of their choices. The Church also reads the psalm Christologically: Acts 1:20 quotes verse 8, let another take his place of leadership, with reference to Judas. In this reading, Judas is the arch-betrayer whose fate is described, not desired. The psalm ends, however, not with curses but with a personal resolution that the whole community of the Church can adopt: With my mouth I will greatly extol the LORD; in the great throng of worshippers I will praise him. The psalmist's ultimate response to being wronged is praise. That is always the final word.
Brothers and sisters, when you have been slandered, when good has been repaid with evil, the temptation is to nurse the wound or seek revenge. The psalmist brings his wound directly to God and leaves the judgment there. Then he turns to praise. Leave what needs to be left with God. Turn your mouth to the praise that is his due. The great throng of worshippers is waiting.
Lord God, you hear the poor and the needy. When we are slandered and wronged, receive our complaint, take up our cause, and let our mouths return quickly to praise. You stand at the right hand of the needy, to save him from those who condemn him. Through Christ our Lord. Amen.