Prove me, O Lord, and try me; burn my reins and my heart.

“Above, the Psalmist proposed a prayer against tribulations; but here, that his prayer might be more acceptable, he sets forth his own justice. The title is plain, because it is not new. Concerning this, then, the Psalmist does two things. First he sets forth in general his whole intention. Second he expounds it in particular, at the words "I have not sat with the council." Concerning the first he does three things. First he asks for judgment. Second he alleges his justice, at "for I." Third he excuses his presumption, at "for thy mercy." Now David, speaking in his own person or in that of the just man, seeing himself mixed in with sinners in place, though not in merit, asks to be distinguished from them; hence he says, "Judge me, O Lord," that is, distinguish me from them. But against this: "Enter not into judgment with thy servant, for in thy sight no man living shall be justified," Psalm 142. I answer that judgment is twofold, namely of severity and of strict rigor: and this judgment he does not ask for, because no one could bear it; the other is the judgment of mercy and of discussion: and this he asks for. Jeremiah 10: "Correct me, O Lord, yet in judgment, and not in thy fury," that is, not in severity. And he sets forth his innocence; and therefore he says, "for I have entered into my innocence," that is, I have progressed in my innocence, or I have entered, because our life is a certain progression. Proverbs 4: "I will lead thee by the paths of equity, which when thou shalt have entered," and so on. And this in my innocence, which I propose to keep: Job 22: "The innocent shall be saved, and he shall be saved in the cleanness of his hands." "I shall not be weakened": Jerome has, "I shall not fail," namely in keeping this innocence: Job 27: "Until I fail I will not depart from it": and this I shall do not by my own strength, but by confidence in divine help, because "trusting in the Lord, I shall not be weakened": 1 Maccabees 2: "All that hope in him shall not be weakened." But against this: this seems to be presumption: Job 9: "If I would justify myself, my own mouth shall condemn me." I answer that the alleging of innocence can sometimes proceed from pride, namely when someone attributes it to himself, and this is evil; sometimes from divine mercy, and this is good; and therefore he adds, "for thy mercy." But how do you know that you are innocent? "Prove me, O Lord," you know this. And he sets down three things: namely proof, tribulation, and temptation. The second follows from the first, the third from the second. He says therefore, "Prove me, O Lord," not that thou mayest learn anything about me from this, but that thou mayest show it to others. Now a man is best proved through temptation, which is the taking of an experiment; temptation is the taking of an experiment concerning that which someone does not know; but proof is of that which one knows, by the manifestation of virtue. And therefore he says, "try me," namely to this end, that I may appear proved to myself and to others: for God does not tempt to evil: James 1: "For God is not a tempter of evils"; but he is said to tempt when certain things are shown by reason of immense difficulty. Now this temptation comes about through fire, as is said in Wisdom 3: "As gold in the furnace he hath proved them." And therefore he says, "burn my reins and my heart," that is, send in tribulations, through which it may become clear what is in my heart and in my reins. To the heart is attributed thought, to the reins delight. And this appears through tribulations, because those who delight in earthly things are greatly disturbed when they lose them, but not those who do not delight in them. Or it can be referred to the fire of the Holy Spirit: Luke 12: "I am come to cast fire on the earth": as if to say: lest I fail in tribulations, bring aid, send the fire which may burn up whatever of carnality is in my delights and vanities in thought. "For." Here he excuses himself in two ways for asking to be tried. First from his own thought, because he thinks on the mercy of God, when he says, "for thy mercy is before my eyes," as if to say: I ask to be tried for this reason, because I trust in thy mercy, which always brings about an increase together with the temptation: Isaiah 63: "I will remember the mercies of the Lord, the praise of the Lord for all that the Lord hath rendered to me." Likewise from love of justice. "And I have been well pleased in thy truth," that is, if thou punish me for my sins, it pleases me; if I am tried, I know that thou wilt reward me. "I have not." Here he explains his intention in particular. And first he sets down his innocence. Second he sets down his petition, at "destroy not my soul with the wicked, O God." He shows, then, his innocence. And first through withdrawal from evils. Second through drawing near to good, at "I will wash." Now there is a threefold kind of evil, according to three sins. For sin is either against God, or against one's neighbor, or against oneself. Against oneself are the sins of vanity, by which a man vainly delights in earthly things; and of these he says, "I have not sat with the council of vanity," as if to say: I do not say that I have not been with them in some measure, because it cannot happen that a man does not at some time vainly delight in earthly things; but he says, "I have not sat": Tobit 3: "I never mingled myself with them that play, neither did I make myself a partaker with them that walk in lightness." Sins which are against one's neighbor are sins that are generated by deed; hence he says, "and with them that do unjust things I will not go in," that is, not only have I not sat, etc., but I have not even gone in, that is, I have in no way mingled myself with them: Proverbs 1: "My son, if sinners shall entice thee, walk not with them." Likewise the aforesaid sins are thought in the heart; hence he says, "I have hated the assembly of the malignant," that is, the congregation of the malignant: Psalm 118: "I have hated the unjust," that is, the fault and the iniquity. Third he sets down the sin against God, and this is impiety; and therefore he says, "and with the wicked," that is, heretics and schismatics, "I will not sit," that is, I will not communicate with their doctrines: Hebrews 13: "Be not led away with divers and strange doctrines." "I will wash." Above the Psalmist showed his innocence by the fact that he separated himself from evils; here, however, he shows it by the fact that he applies himself to goods. And because the goods by whose application we are made just are divine goods, therefore he speaks of his application to them. Concerning this he does two things. First he sets down his zeal. Second the effect, at "Lord, I have loved the beauty of thy house." Concerning the first he does three things. First he proposes his disposition toward the divine worship. Second he sets down the worship itself, at "I will compass." Third the fruit, at "that I may hear the voice of praise." Disposition comes about through purity and innocence: Psalm 14: "Lord, who shall dwell in thy tabernacle," and so on. Psalm 23: "The innocent in hands, and clean of heart." And therefore, that he may approach as one pure, he treats of purity. He says therefore, "I will wash my hands among the innocent," that is, my works, which are chiefly washed by God, through the grace which he infuses: Psalm 50: "Wash me yet more from my iniquity," and so on. Likewise they are washed by us through penance: Isaiah 1: "Wash yourselves, be clean," and so on. "I will wash," therefore, that is, I will apply penance so that they may be washed. And this, "among the innocent," because character is formed by association: Psalm 17: "With the innocent thou wilt be innocent," and so on. And thus washed, I will approach the divine worship. "And I will compass thy altar, O Lord." Here he speaks of the material altar, and it is said, "I will compass thy altar, O Lord," because either he prays, or he stands beside it; Ecclesiasticus 50, concerning Simon the high priest, "he himself standing near the altar." And therefore the priest, when he approaches the sacrament, says "I will wash," and so on. Or it can be understood of the spiritual altar. The altar is in the temple: and just as there is a threefold temple, so there is a threefold altar. The first is the just man: 1 Corinthians 6: "Know you not that your members are the temple of the Holy Ghost?" The altar of this temple is the heart: Leviticus 6: "Fire," namely of charity, "on the altar," that is, in the heart, "shall always burn." This altar we ought to compass, or stand beside it, that is, adorn it, always returning to Christ: Proverbs 4: "With all watchfulness keep thy heart, because life issueth out from it." The other temple is the Church: and the altar of this temple is Christ: Hebrews, last chapter: "We have an altar, whereof they have no power to eat who serve the tabernacle." Or it is faith. And this we ought to compass, so that we may be about it with our whole heart. The third temple is God himself: Apocalypse 21: "I saw a temple in it, the Lord God Almighty is the temple thereof," and so on: and the altar of this is the mercy of God. And this we ought to compass with desire of mind: Psalm 144: "The Lord is sweet to all, and his tender mercies are over all his works." Consequently he shows the fruit: and it is a twofold fruit, namely to hear and to declare; hence he says, "that I may hear the voice of praise." And this, according to the letter, concerns the material altar, because this sacrifice is most acceptable to God: Psalm 49: "The sacrifice of praise shall honor me." Likewise the praise which the Holy Spirit speaks in us: Psalm 84: "I will hear what the Lord God will speak in me." Likewise, in heaven: Isaiah 35: "Joy and gladness," and so on. Or, "I may hear the voice of praise," that is, of Christ praising me: and this will be at the judgment, when he shall say, "I was hungry," and so on, Matthew 25. But Apocalypse, last chapter, it is said: "He that heareth, let him say, Come." Hence we hear to this end, that we may say to others: Isaiah 21: "What I have heard of the Lord of hosts, the God of Israel, I have declared unto you." And therefore he adds, "that I may tell all thy wondrous works": Ecclesiasticus 42: "Did not God make the saints to declare... and so on. And he says, "all wondrous works," as regards affection or endeavor, not as regards effect, because he himself is greater than all praise. "Lord." Here he shows the affection which he has toward the divine worship: which, that it may be fitting, ought to be an affection of love. Wherefore he says, "Lord, I have loved the beauty of thy house." Dionysius: "The good and the beautiful are lovable to all." Hence every man loves the beautiful: carnal men love carnal beauty, spiritual men love spiritual beauty, and this is the beauty of the house of God: Numbers 24: "How beautiful are thy tabernacles, O Jacob, and thy tents, O Israel! As woody valleys, as watered gardens near the rivers, as tabernacles which the Lord hath pitched." Now this beauty is that of good works, or of divine gifts, or of the saints themselves; because all these are, as it were, a certain beauty of the house of God. All these things, therefore, I have loved, that they might make me fit for the beauty of the house of God. Thus, then, the affection is shown, because there is love, and beauty, and comeliness. But it must be known that this beauty comes from the indwelling of God; just as a house is not beautiful unless it be inhabited: hence, either I have loved myself so that thou mayest dwell in me, or I have loved my homeland so that I may dwell there, or that I may tend toward it. And therefore he says, "and the place where thy glory dwelleth": and all these things, that is, good works, the gifts of God, and the saints themselves, are the beauty of the house of God, insofar as the divine grace, which beautifies as light does, shines forth in them, as Ambrose says, that without light all things are ugly: Ezekiel 43: "The glory of the Lord went in by the gate." "Take not away." Here he explains the petition of judgment which he asks; and he expounds what kind of judgment he asked. And he asks two things. First he asks to be separated from the evils which can come to pass in the future. Second from the evils which he suffers in the present, at "redeem." First, then, he sets down the petition. Here it must be known that punishment from God is reserved for two kinds of men: namely those who are impious or sinners against God: Ezekiel 18: "The wickedness of the wicked shall be upon him." And therefore he says, "take not away," etc.: as if to say: if here I am afflicted and suffer earthly evils along with the wicked, nevertheless take not away my soul with them. Likewise punishment is reserved for the impious against their neighbor: therefore he says, "and my life with bloody men": Psalm 54: "Bloody and deceitful men." Here are reckoned all who offend against their neighbor, in whatever way. Now there is a threefold blood. One which is caused from food and drink: hence food and drink are called the blood of the poor: Ecclesiasticus 34: "The bread of the nations is the life of the poor: he that defraudeth him thereof is a man of blood." The second is the blood of man; and this the murderer sheds. The third is the blood of seed for the preservation of the species, and this the fornicator sheds, because he does not act for the sake of offspring. "In whose hands are iniquities": as if to say: I ask this, namely that I be separated from these then, because now I am separated in conduct and life, since in their hands are iniquities, that is, they are greatly prone to evil: Proverbs 1: "Their feet run to evil, and they make haste to shed blood": Isaiah 59: "Works of iniquity are in their hands." Likewise there is an inclination of their affection toward worldly things; hence he says, "their right hand is filled with gifts": Job 15: "Fire shall devour the tabernacles of them that love to take gifts." Or, "their right hand is filled with gifts": as if to say, although they themselves are wicked, yet thou givest them temporal things, and in these consists their reward: Matthew 6: "They have received their reward." Consequently he describes himself, saying, "but as for me, I have entered into my innocence": as if to say, I ask this, that just as thou preparest evils for them, so thou mayest prepare good things for me, as it is said in Psalm 83: "He will not deprive of good things them that walk in innocence." Consequently he asks to be freed from present evils. The evils which befall a man can be twofold; for they are either exterior evils, and from these he asks to be redeemed; hence he says, "redeem me," as a servant from the evils that press upon me. Or it concerns the redemption of the human race. Or they are interior evils, and from these he asks to be freed; hence he says, "have mercy on me," because misery properly regards interior evil: Proverbs 14: "Sin maketh nations miserable." "For my foot." Here is set down the reason why he asks this; and it is twofold. One concerns the past, which is the rectitude of life; hence he says, "my foot," that is, my affection, or my course, "hath stood in the direct way." Likewise concerning the future he proposes to serve thee always; hence he says: "in the churches I will bless thee, O Lord," that is, before many: Psalm 39: "I have declared thy justice in a great church." And he speaks in the plural, on account of the multitude of the particular churches, as is said in Apocalypse 3.”

“Examine me, O Lord,.... His cause, his integrity, and trust in the Lord, as silver and gold are examined by the touchstone, the word of God, which is the standard of faith and practice; and prove me; or "tempt me" (r); as Abraham was tempted by the Lord; and his faith in him, and fear of him, and love to him, were proved to be true and genuine; try my reins and my heart; the thoughts, desires, and affections of it, as gold and silver are tried in the furnace; and so God sometimes tries the faith and patience of his people by afflictive providences; and this examination, probation, and trial, are made by him, not for his own sake, who knows the hearts and ways of all men; but for the sake of others, to make known either to themselves or others the truth of grace that is in them, and the uprightness of their hearts and ways; and it was on this account the psalmist desired to pass under such an examination. (r) "tenta me", Pagninus, Montanus, Junius & Tremellius, &c.”

“Burn, like gold in the furnace. (Berthier) — Purify all my affections and thoughts with the fire of divine love. (St. Augustine; St. Jerome) — Make my dispositions known to the world. I have done no one any harm. (Calmet) — I take thee for the arbiter of my cause with respect to Saul, whom I have not injured. Still, as I may not be innocent, do thou try me, as thou thinkest proper. (Worthington)”