13 For this purpose he briefly sketches in what follows the troubles of Christ's body. For it is not in the Head alone that they took place, since it is said to Saul too, “Why do you persecute Me?” and Paul himself, as if placed as an elect member in the same body, says, “That I may fill up that which is behind of the afflictions of Christ in my flesh.” “Why then, Lord, have You cast off my soul? Why hidest Thou Your face from me?”
“I am poor, and in toils from my youth up: and when lifted up, I was thrown down, and troubled”.
“Your wraths went over me: Your terrors disturbed me”.
“They came round about me all day like water: they compassed me about together”.
“A friend You have put far from me: and mine acquaintance from my misery”. All these evils have taken place, and are happening in the limbs of Christ's body, and God turns away His face from their prayers, by not hearing as to what they wish for, since they know not that the fulfilment of their wishes would not be good for them. The Church is “poor,” as she hungers and thirsts in her wanderings for that food with which she shall be filled in her own country: she is “in toils from her youth up,” as the very Body of Christ says in another Psalm, “Many a time have they overcome me from my youth.” And for this reason some of her members are lifted up even in this world, that in them may be the greater lowliness. Over that Body, which constitutes the unity of the Saints and the faithful, whose Head is Christ, go the wraths of God: yet abide not: since it is of the unbelieving only that it is written, that “the wrath of God abides upon him.” The terrors of God disturb the weakness of the faithful, because all that can happen, even though it actually happen not, it is prudent to fear; and sometimes these terrors so agitate the reflecting soul with the evils impending around, that they seem to flow around us on every side like water, and to encircle us in our fears. And as the Church while on pilgrimage is never free from these evils, happening as they do at one moment in one of her limbs, at another in another, he adds, “all day,” signifying the continuation in time, to the end of this world. Often too, friends and acquaintances, their worldly interests at stake, in their terror forsake the Saints; of which says the Apostle, “all men forsook me: may it not be laid to their charge.” But to what purpose is all this, but that early in the morning, that is, after the night of unbelief, the prayers of this holy Body may in the light of faith prevent God, until the coming of that salvation, which we are at present saved by hoping for, not by having, while we await it with patience and faithfulness. Then the Lord will not repel our prayers, as there will no longer be anything to be sought for, but everything that has been rightly asked, will be obtained: nor will He turn His face away from us, since we shall see Him as He is: nor shall we be poor, because God will be our abundance, all in all: nor shall we suffer, as there will be no more weakness: nor after exaltation shall we meet with humiliation and confusion, as there will be no adversity there: nor bear even the transient wrath of God, as we shall abide in His abiding love: nor will His terrors agitate us, because His promises realized will bless us: nor will our friend and acquaintance, being terrified, be far from us, where there will be no foe to dread.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)