8 “Blessed is the man that makes the name of the Lord his hope, and who has not regarded vanities and lying madnesses.” For whence is it that “madness” is called “lying”? Insanity is a lying thing, even as it is sanity that sees the Truth. For what you see as good things, you are deceived; you are not in your sound senses: a violent fever has driven you to frenzy: that which you are in love with is not a reality. Thou applaudest the charioteer; you cheer the charioteer; you are madly in love with the charioteer.
It is “vanity;” it is “a lying madness.” “It is 'not'” (he cries). “Nothing can be better; nothing more delightful.” What can I do for one in a state of high fever? Pray ye for such persons, if you have any feelings of compassion in you. For the physician himself also in a desperate case generally turns to those in the house, who stand around weeping; who are hanging on his lips to hear his opinion of the patient who is sick and in danger. The physician stands in a state of doubt: he sees not any good to promise; he fears to pronounce evil, lest he should excite alarm.
He devises a thoroughly modest sentence: “The good God can do all things. Pray ye for him.” Which then of these madmen shall I check? Which of them will listen to me? Which of them would not call us miserable? Because they suppose us to have lost great and various pleasures, of which they are madly fond, in that we are not as madly in love with them as they are: and they do not see that they are “lying” pleasures....“And has not respected vanities, and lying madnesses.” “Such a one has won,” he cries; “he harnessed such and such a horse,” he proclaims aloud.
He would fain be a kind of diviner; he aspires to the honours of divination by abandoning the fountain of Divinity; and he frequently pronounces an opinion, and is frequently mistaken. Why is this? Even because they are “lying madnesses.” But why is it that what they say sometimes comes true? That they may lead astray the foolish ones; that by loving the semblance of truth there, they may fall into the snare of falsehood: let them be left behind, let them be “given over,” let them be “cut off.”
If they were members of us, they must be mortified. “Mortify,” he says, “your members which are upon the earth.” Let our God be our hope. He who made all things, is better than all! He who made what is beautiful, is more beautiful than all that is such. He who made whatever is mighty, is Himself mightier. He who made whatever is great, is Himself greater. He will be unto you everything that you love. Learn in the creature to love the Creator; and in the work Him who made it. Let not that which has been made by Him detain your affections, so that you should lose Him by whom you yourself were made also. “Blessed,” then, “is the man that makes the Name of the Lord his trust, and has not respected vanities and lying madnesses.”...
Source: The Enarrations, or Expositions, on the Psalms (New Advent)