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1 The fool hath said in his heart, There is no God. Corrupt are they, and have done abominable iniquity: there is none that doeth good. 2 God looked down from heaven upon the children of men, to see if there were any that did understand, that did seek God. 3 Every one of them is gone back: they are altogether become filthy; there is none that doeth good, no, not one. 4 Have the workers of iniquity no knowledge? who eat up my people as they eat bread: they have not called upon God. 5 There were they in great fear, where no fear was: for God hath scattered the bones of him that encampeth against thee: thou hast put them to shame, because God hath despised them. 6 Oh that the salvation of Israel were come out of Zion! When God bringeth back the captivity of his people, Jacob shall rejoice, and Israel shall be glad.
[AD 56] Romans on Psalms 53:1-3
What then? are we better than they? No, in no wise: for we have before proved both Jews and Gentiles, that they are all under sin; As it is written, There is none righteous, no, not one: There is none that understandeth, there is none that seeketh after God. They are all gone out of the way, they are together become unprofitable; there is none that doeth good, no, not one. Their throat is an open sepulchre; with their tongues they have used deceit; the poison of asps is under their lips: Whose mouth is full of cursing and bitterness: Their feet are swift to shed blood: Destruction and misery are in their ways: And the way of peace have they not known: There is no fear of God before their eyes. [Psalms 53:1-3] Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world may become guilty before God. Therefore by the deeds of the law there shall no flesh be justified in his sight: for by the law is the knowledge of sin. But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets; Even the righteousness of God which is by faith of Jesus Christ unto all and upon all them that believe: for there is no difference: For all have sinned, and come short of the glory of God; Being justified freely by his grace through the redemption that is in Christ Jesus: Whom God hath set forth to be a propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God; To declare, I say, at this time his righteousness: that he might be just, and the justifier of him which believeth in Jesus.
[AD 430] Augustine of Hippo on Psalms 53:1
"The unwise man has said in his heart, There is no God" [Psalm 53:1]. Such sort is it of men amid whom is pained and groans the Body of Christ. If such is this sort of men, of not many do we travail; as far as seems to occur to our thoughts, very few there are; and a difficult thing it is to meet with a man that says in his heart, "There is no God;" nevertheless, so few there are, that, fearing amid the many to say this, in their heart they say it, for that with mouth to say it they dare not. Not much then is that which we are bid to endure, hardly is it found: uncommon is that sort of men that say in their heart, "There is no God." But, if it be examined in another sense, is not that found to be in more men, which we supposed to be in men few and uncommon, and almost in none? Let them come forth into the midst that live evil lives, let us look into the doings of profligate, daring, and wicked men, of whom there is a great multitude; who foster day by day their sins, who, their acts having been changed into habit, have even lost sense of shame: this is so great a multitude of men, that the Body of Christ, set amid them, scarce dares to censure that which it is not constrained to commit, and deems it a great matter for itself that the integrity of innocence be preserved in not doing that which now, by habit, either it does not dare to blame, or if it shall have dared, there breaks out the censure and recrimination of them that live evil lives, more readily than the free voice of them that live good lives. And those men are such as say in their heart, "There is no God." Such men I am confuting. Whence confuting? That their doings please God, they judge. He does not therefore affirm, "some say," but "The unwise man has said in his heart, There is no God." Which men do so far believe there is a God, that the same God they judge with what they do to be pleased. But if you being wise dost perceive, how "the unwise man has said in his heart, There is no God," if you give heed, if you understand, if you examine; he that thinks that evil doings please God, Him he does not think to be God. For if God is, He is just; if He is just, injustice displeases Him, iniquity displeases. But you, when you think that iniquity pleases Him, dost deny God. For if God is one Whom iniquity displeases, but God seems not to you to be one whom iniquity displeases, and there is no God but one whom iniquity displeases, then when you say in your heart, God does countenance my iniquities, you say nothing else than, "There is no God."

[AD 500] Salvian the Presbyter on Psalms 53:1
To such people the word of the prophet can be applied most fittingly: “The fool says in his heart, there is no God.” They who say that nothing is seen by God almost deprive him of eyes and even take away substance from him. For when they say he sees nothing, they say he does not exist at all. Although no evil deed is based on reason, because crime cannot be joined with reason, there is no sin, I believe, more irrational or senseless. What is more insane than for anybody, who does not deny that God is the creator of the universe, to deny his governance? How does he admit that God created the world and neglects what he created? As if, indeed, he took pains in creating all things so that he would neglect what he had made!

[AD 430] Augustine of Hippo on Psalms 53:2
Let us advert also to that sense, which concerning Christ our Lord Himself, our Head Himself, does present itself. For when Himself in form of a servant [Philippians 2:7] appeared on earth, they that crucified Him said, "He is not God." Because Son of God He was, truly God He was. But they that are corrupted and have become abominable said what? "He is not God:" let us slay Him, "He is not God." You have the voice of these very men in the book of Wisdom. For after there had gone before the verse, "The unwise man has said in his heart, There is no God;" as if reasons were required why the unwise man could say this, he has subjoined, "Corrupted they are, and abominable have become in their iniquities" [Psalm 53:2]. Hear ye those corrupted men. "For they have said with themselves, not rightly thinking:" [Wisdom 2:1] corruption begins with evil belief, thence it proceeds to depraved morals, thence to the most flagrant iniquities, these are the grades. But what with themselves said they, thinking not rightly? "A small thing and with tediousness is our life." [Wisdom 2:1] From this evil belief follows that which also the Apostle has spoken of, "Let us eat and drink, for tomorrow we shall die." [1 Corinthians 15:32] But in the former passage more diffusely luxury itself is described: "Let us crown us with roses, before they be withered; in every place let us leave the tokens of our gladness." [Wisdom 2:8-9] After the more diffuse description of that luxury, what follows? "Let us slay the poor just man:" [Wisdom 2:10] this is therefore saying, "He is not God." Soft words they seemed but now to say: "Let us crown us with roses, before they be withered." What more delicate, what more soft? Would you expect, out of this softness, Crosses, swords? Wonder not, soft are even the roots of brambles; if any one handle them, he is not pricked: but that wherewith you shall be pricked from thence has birth. "Corrupted," therefore, are those men, "and abominable have become in their iniquities." They say, "If Son of God He is, let Him come down from the Cross." [Matthew 27:40] Behold them openly saying, "He is not God."...

[AD 430] Augustine of Hippo on Psalms 53:3-4
"The Lord from Heaven has looked forth upon the sons of men, that He might see if there is one understanding and seeking after God" [Psalm 53:3]. What is this? "Corrupted they are," all these that say, "There is no God"? And what? Did it escape God, that they had become such? Or indeed to us would their inward thought be opened, except by Him it were told? If then He understood, if then He knew, what is this which has been said, "that He might see"? For the words are of one inquiring, of one not knowing. "God from Heaven has looked forth," etc. And as though He had found what He sought by looking upon, and by looking down from Heaven, He gives sentence: "All men have gone aside, together useless they have become: there is not one that does good, not so much as one" [Psalm 53:4]. Two questions arise somewhat difficult: for if God looks out from Heaven, in order that He may see if there is one understanding or seeking after God; there steals upon an unwise man the thought, that God knows not all things. This is one question: what is the other? If there is not one that does good, is not so much as one; who is he that travails amid bad men? The former question then is solved as follows: ofttimes the Scripture speaks in such manner, that what by the gift of God a creature does, God is said to do....For hence has been said the following also, "For the Spirit searches all things, even the depth of God;" [1 Corinthians 2:10] not because He that knows all things searches, but because to you has been given the Spirit, which makes you also to search: and that which by His own gift you do, He is said to do; because without Him you would not do it: therefore God is said to do, when you do. And because this by the gift of God you doest, God from heaven is "looking forth upon the sons of men." The former question then, according to our measure, thus has been solved.

[AD 430] Augustine of Hippo on Psalms 53:5
"Shall not all know that work iniquity, that devour My people for the food of bread"? [Psalm 53:5]....There is therefore here a people of God that is being devoured. Nay, "There is not one that does good, there is not so much as one." We reply by the rule above. But this people that is devoured, this people that suffers evil men, this that groans and travails amid evil men, now out of sons of men have been made sons of God: therefore are they devoured. For, "The counsel of the needy man you have confounded, because the Lord is his hope." For ofttimes, in order that the people of God may be devoured, this very thing in it is despised, that it is the people of God. I will pillage, he says, and despoil; if he is a Christian, what will he do to me?...But what follows? "I will convince you, and will set you before your face." You will not now know so as you should be displeasing to yourself, you shall know so as you may mourn. For God cannot but show to the unrighteous their iniquity. If He is not to show, who will they be that are to say, "What has profited us pride, and what has boasting of riches bestowed upon us?" [Wisdom 5:8] For then shall they know, that now will not know. "Shall not all know?" etc. Why has He added, "for the food of bread"? As it were as bread, they eat My people. For all other things which we eat, we can eat now these, now those; not always this vegetable, not always this flesh, not always these apples: but always bread. What is then, "Devour My people for the food of bread"? Without intermission, without cessation they devour.

[AD 431] Paulinus of Nola on Psalms 53:5
Perhaps he calls them saints in this psalm in the same way that he calls them just in the Gospel when he says, “I am not come to call the just but sinners,” that is, those just who boast of the holiness of their race and the letter of the Law, to whom it is said, “Do not boast of your father Abraham, for God is able of these stones to raise up children to Abraham.” This type is exemplified in the Pharisee6 who recited his good works in the temple, as if recalling them to an ignorant Lord, not praying to be heard but demanding the reward due to his good conduct. Yet, this was displeasing to God because he tore down by his pride what he had built up by his justice; he did not do this silently but at the top of his voice; and it is evident that he did not speak to divine ears, because he wished to be heard by people. Hence, he was not pleasing to God because he was pleasing to himself. “For God has scattered the bones of people pleasing to themselves; they have been confounded,” he says, “because he has despised them,” who “does not despise a contrite and humbled heart.”

[AD 580] Martin of Braga on Psalms 53:5
Such a person not only cuts himself off from the rewards of his virtues but even lays himself open to being condemned to eternal punishment, because the good action, which ought to be performed in consideration of a merciful God, has been performed in order to gain praise. Take away the favors, take away people’s admiration, and you will find few who do something good either for the love of God, or barring that, for fear of God; yet no less is the blame with which we are tainted, because we place people before God and human glory before heavenly glory. This disease of pride is acute; it poisons from either side, and it wounds when least expected. For some boast of themselves because they are good, others because they are bad. Of the good who boast, it is said, “For God has scattered the bones of those who are pleased with themselves.” Of the evil who boast it is said, “For the wicked person is praised in the desires of his soul, and the worker of injustice shall be blessed.” There are also the words of the apostle: “Their god is the belly, their glory is in their shame.”

[AD 430] Augustine of Hippo on Psalms 53:6-7
For this reason what follows concerning them? "There have they feared with fear, where there was no fear" [Psalm 53:6]. For is there fear, if a man lose riches? There is no fear there, and yet in that case men are afraid. But if a man lose wisdom, truly there is fear, and in that case he is not afraid....You have feared to give back money, and hast willed to lose fidelity. The Martyrs took not away property of other persons, but even their own they despised that they might not lose fidelity: and it was too little to lose money, when they were proscribed; they took also their life when they suffered: they lost life, in order that unto everlasting life they might find it. [Matthew 10:39] Therefore there they feared, where they ought to have been afraid. But they that of Christ have said, "He is not God," have there feared where was no fear. For they said, "If we shall have let Him go, there will come the Romans, and will take away from us both place and kingdom." [John 11:48] O folly and imprudence saying in its heart, "He is not God"! You have feared to lose earth, you have lost Heaven: you have feared lest there should come the Romans, and take away from you place and kingdom! Could they take away from you God? What then remains? What but that thou confess, that you have willed to keep, and by keeping ill hast lost? For you have lost both place and nation by slaying Christ. For you did will rather to slay Christ, than to lose place; and you have lost place, and nation, and Christ. In fearing, they have slain Christ: but wherefore this? "For God has scattered the bones of them that please men." Willing to please men, they feared to lose their place. But Christ Himself, of whom they said, "He is not God," willed rather to displease such men, as they were: sons of men, not sons of God, He willed rather to displease. Thence were scattered their bones, His bones no one has broken. "They were confounded, for God has despised them." In very deed, brethren, as far as regards them, great confusion has come to them. In the place where they crucified the Lord, whom for this cause they crucified, that they might not lose both place and nation, the Jews are not. "God," therefore, "has despised them:" and yet in despising He warned them to be converted. Let them now confess Christ, and say, He is God, of whom they said, "He is not God." Let them return to the inheritance of their fathers, to the inheritance of Abraham, of Isaac, and of Jacob, let them possess with these very persons life eternal: though they have lost life temporal. Wherefore this? Because out of sons of men have been made sons of God. For so long as they remain, and will not, there is not one that does good, there is not so much as one. "They were confounded, for God has despised them." And as though to these very persons He were turned, He says, "Who shall give out of Sion salvation to Israel?" [Psalm 53:7]. O you fools, you revile, insult, buffet, besmear with spittings, with thorns ye crown, upon the Cross ye lift up; whom? "Who shall give out of Sion salvation to Israel?" Shall not That Same of whom you have said, "He is not God"? "In God's turning away the captivity of His people." For there turns away the captivity of His people, no one but He that has willed to be a captive in your own hands. But what men shall understand this thing? "Jacob shall exult, and Israel shall rejoice." "Israel;" the true Jacob, and the true Israel, that younger, to whom the elder was servant, [Genesis 25:23] shall himself exult, for he shall himself understand.