13 Is any among you afflicted? he means that there is no time in which God does not invite us to himself. For afflictions ought to stimulate us to pray; prosperity supplies us with an occasion to praise God. But such is the perverseness of men, that they cannot rejoice without forgetting God, and that when afflicted they are disheartened and driven to despair. We ought, then, to keep within due bounds, so that the joy, which usually makes us to forget God, may induce us to set forth the goodness of God, and that our sorrow may teach us to pray. For he has set the singing of psalms in opposition to profane and unbridled joy; and thus they express their joy who are led, as they ought to be, by prosperity to God.