10 What then have all those deaths of the martyrs accomplished? Listen: “As the fatness of the earth is spread over the earth, our bones have been scattered beside the pit”. “The bones” of the martyrs, that is, the bodies of the witnesses of Christ. The martyrs were slain, and they who slew them seemed to prevail. They prevailed by persecution, that the words of Christ might prevail by preaching. And what was the result of the deaths of the saints? What means, “the fatness of the earth is spread over the earth”? We know that everything that is refuse is the fatness of the earth. The things which are, as it were, contemptible to men, enrich the earth....“Precious in the sight of the Lord is the death of His saints.” As it is contemptible to the world, so is it precious to the husbandman. For he knows the use thereof, and its rich juice; he knows what he desires, what he seeks, whence the fertile crop arises; but this world despises it. Do you not know that “God has chosen the contemptible things of the world, and those which are not, like as those which are, that the things which are may be brought to nought”? From the dunghill was Peter lifted up, and Paul; when they were put to death, they were despised: now, the earth having been enriched by them, and the cross of the Church springing up, behold, all that is noble and chief in the world, even the emperor himself, comes to Rome, and whither does he hasten? To the temple of the emperor, or the memorial of the fisherman?
11. “For unto You, Lord, are my eyes; in You have I hoped, take not Thou away my life”. For they were tortured in persecutions, and many failed. It occurs to him that many have failed, many have been in hazard, and as it were in the midst of the tribulation of persecution is sent forth the voice of one praying; “For unto You, Lord, are my eyes:” I care not what they threaten who stand around, “unto You, Lord, are my eyes.” More do I fix my eye on Your promises than on their threats. I know what You have suffered for me, what You have promised me.
12. “Keep me from the trap which they have laid for me”. What was the trap? “If you consent, I spare you.” In the trap was set the bait of the present life; if the bird love this bait, it falls into the trap: but if the bird be able to say, “The day of man have I not desired: You know:” “He shall pluck his feet out of the net,” etc. Two things he has mentioned to be distinguished the one from the other: the trap he said was set by persecutors; the stumbling-blocks came from those who have consented and apostatised: and from both he desires to be guarded. On the one side they threaten and rage, on the other consent and fall: I fear lest the one be such, that I fear him; the other such, that I imitate him. “This I do to you, if you consent not.” “Keep me from the trap,” etc. “Behold, your brother has already consented.” “And from the stumbling-blocks,” etc.
13. “Sinners shall fall into his nets”. Not all sinners, certain sinners, who are so great sinners, as to love this life to such a degree as to prefer it to everlasting life, “shall fall into his trap.” But what do you say? Shall they that are such, do you think, fall into his nets? What of Your disciples, O Christ? Behold, when persecution was raging, when they all “left You alone, and went every one to his own:” lo! They who were closest to You, in Your trial and persecution, when Your enemies demanded You to be crucified, abandoned You. And that bold one, who had promised You that he would go with You even unto death, heard from the Physician what was being done in him, the sick man. For being in a fever, he had said he was whole; but the Lord touched the vein of his heart. Then came the trial; then came the test; then came the accusation; and now, questioned not by some great power, but by a humble slave, and that a woman, questioned by a handmaid, he yielded; he denied thrice....“He wept bitterly,” it says. Not yet was he fitted to suffer. To him was said, “You shall follow Me afterwards.” Hereafter he was to be firm, having been strengthened by the Lord's Resurrection. Not yet then was it time that those “bones” should be “scattered beside the pit.” For see how many failed, even to those who first hung on His mouth; even they failed. Wherefore? “I am alone, until I pass over:” for this follows in the Psalm....
Source: The Enarrations, or Expositions, on the Psalms (New Advent)