3 “My soul has thirsted for You”. Behold that desert of Idumæa. See how here he thirsts: but see what good thing is here, “Hath thirsted for You.” For there are they that thirst, but not for God. For every one that wills anything to be granted to him, is in the heat of longing; the longing itself is the thirst of the soul. And see ye what longings there are in the hearts of men: one longs for gold, another longs for silver, another longs for possessions, another inheritance, another abundance of money, another many herds, another a wife, another honours, another sons. You see those longings, how they are in the hearts of men. All men are inflamed with longing, and scarce is found one to say, “My soul has thirsted for You.” For men thirst for the world: and perceive not themselves to be in the desert of Idumæa, where their souls ought to thirst for God....
Source: The Enarrations, or Expositions, on the Psalms (New Advent)