18 To wit, “because of deceitfulness You have set upon them”. Because deceitful they are, that is fraudulent; because deceitful they are, they suffer deceits. What is this, because fraudulent they are they suffer a fraud? They desire to play a fraud upon mankind in all their naughtinesses, they themselves also suffer a fraud, in choosing earthly good things, and in forsaking the eternal. Therefore, brethren, in their very playing off a fraud they suffer a fraud. In that which but now I said, brethren, “What manner of wit has he who to gain a garment does lose his fidelity?” has he whose garment he has taken suffered a fraud, or he that is smitten with so great a loss? If a garment is more precious than fidelity, the former does suffer the greater loss: but if incomparably good faith does surpass the whole world, the latter shall seem to have sustained the loss of a garment; but to the former is said, “What does it profit a man if he gain the whole world, but suffer the loss of his own soul?” Therefore what has befallen them? “Because of deceitfulness You have set for them: You threw them down while they were being exalted.” He has not said, You threw them down because they were lifted up: not as it were after that they were lifted up You threw them down; but in their very lifting up they were thrown down. For thus to be lifted up is already to fall.
19. “How have they become a desolation suddenly?”. He is wondering at them, understanding unto the last things. “They have vanished.” Truly like smoke, which while it mounts upward, does vanish, so they have vanished. How does he say, “They have vanished”? In the manner of one who understands the last things: “they have perished because of their iniquity.” “Like as the dream of one rising up”. How have they vanished? As vanishes the dream of one rising up. Fancy a man in sleep to have seen himself find treasures; he is a rich man, but only until he awakes. “Like as the dream of one rising up:” so they have vanished, like the dream of one awaking. It is sought then and it is not: there is nothing in the hands, nothing in the bed. A poor man he went to sleep, a rich man in sleep he became: had he not awoke, he were a rich man: he woke up, he found the care which he had lost while sleeping. And these men shall find the misery which they had prepared for themselves. When they shall have awoke from this life, that thing does pass away which was grasped as if in sleep. “Like as the dream of one rising up.” And that there might not be said, “What then? A small thing does their glory seem to you, a small thing does their state seem to you, small things seem to you inscriptions, images, statues, distinctions, troops of clients?” “O Lord,” he says, “in Your city their image You shall bring to nothing.”...He has taken away the pride of rich men, he gives counsel. As if they were saying, We are rich men, thou dost forbid us to be proud, dost prohibit us from boasting of the parade of our riches: what then are we to do with these riches? Is it come to this, that there is nothing which they may do therewith? “Be they rich,” he says, “in good works; let them readily distribute, communicate.” And what does this profit? “Let them treasure unto themselves a good foundation for the future, that they may lay hold of true life.” Where ought they to lay up treasure for themselves? In that place whereunto he set his eye, when entering into the Sanctuary of God. Let there shudder all our rich brethren, abounding in money, gold, silver, household, honours, let them shudder at that which but now has been said, “You shall bring to nothing their image.” Are they not worthy to suffer these things, to wit that God bring to nothing their image in His city, because also they have themselves brought to nothing the image of God in their earthly city?
20. “Because my heart was delighted”. He is saying with what things he is tempted: “because my heart was delighted,” he says, “my reins also were changed.” When those temporal things delighted me, my reins were changed. It may also be understood thus: “because my heart was delighted” in God, my reins also were changed, that is, my lusts were changed, and I became wholly chaste. “My reins were changed.” And hear how. “And I was brought unto nothing, and I knew not”. I, the very man, who now say these things of rich men, once longed for such things: therefore “even I was brought to nothing” when my steps were almost overthrown. “And I was brought unto nothing, and I knew not.” We must not therefore despair even of them, against whom I was saying such things.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)