Orthodoxos:^[1] Listen now how the prophet praises God at the very beginning of the psalm. He saw with his prophetic eyes the future iniquity of his people and the captivity that was in consequence foredoomed; yet he praised his own Lord for unfailing promises. I will sing, he says, of the mercies of the Lord forever; with my mouth will I make known your faithfulness to all generations, for you have said, Mercy shall be built up forever, your faithfulness you shall establish in the very heavens.

Through all this the prophet teaches that the promise was made by God on account of lovingkindness and that the promise is faithful. Then he goes on to say what he promised, and to whom, introducing God as the speaker. (I have made a covenant with my chosen.) It is the patriarchs that he called chosen; then he goes on, I have sworn to David my servant, and he states concerning what he swore, Your descendants will I establish forever, and build up your throne to all generations.

O such strictness toward the righteous! O such abundant forgiveness toward the sinner! He finds so many different means, without himself changing, to keep the righteous in check and forgive the sinner, by usefully dividing his rich goodness. And listen how. If he frightens the sinner who persists in sins, he brings him to desperation and to the exhaustion of hope. If he blesses the right-eous, he weakens the intensity of his virtue and makes him neglect his zeal, since he considers himself already blessed. For this reason he is merciful to the sinner and frightens the righteous. For he is terrible to all who surround him. And, The Lord is good to the whole world.^[1] He is terrible, David says, to all who surround him. And who are they but the saints? For God, David says, who is glorified in the council of the saints, [is] great and terrible to all who surround him. If he sees someone who has fallen, he extends a loving hand. If he sees someone standing, he brings fear on him. And this reveals righteousness and righteous judgment. He establishes the righteous one with fear, and he raises up the sinner with benevolence.

We suffer these things because of our fault and of our deserving, as the divine judgment has forewarned us, saying, If they have forsaken my law and have walked not in my judgments, if they have profaned my ordinances and have kept not my commands, I will visit their crime with a rod and their guilt with stripes.^[1] We, therefore, who neither please God with our good deeds nor satisfy him for our sins, feel the rods and the lashes. Let us ask from the depth of our heart and with our whole mind the mercy of God because he himself adds this, saying, Yet my kindness I will not take from them.^[2] Let us ask and we receive; and, if there is delay and tardiness in our receiving because we have offended gravely, let us knock because to him who also knocks it is opened,^[3] provided only our prayers and groans and tears knock at the door, in which we ought to persist and to employ much time, provided our prayer is also of one mind.

Not without reason was [the soul]^[1] given horns and hoofs, to bruise all the sheaves of the threshing floor, like the calf of Libanius,^[2] for, unless the sheaves are bruised and the straw winnowed, the corn within cannot appear and be separated. Let the soul that would advance in virtue first bruise and thresh out its superfluous passions that at the harvest it may have its fruits to show. How many weeds choke the good seed! These first must be rooted out, so that they will not destroy the fruitful crop of the soul.^[3]

The careful guardian of the soul then sees how he may restrain [the soul] in its pleasures and cut off its desires, to prevent it being overwhelmed with delight in them. The correction of the father who does not spare the rod is useful, that he may render his son’s soul obedient to the precepts of salvation.^[4] He punishes with a rod, as we read: I shall punish their offenses with a rod. Therefore, one who with a rod strikes an Israelite’s soul on the cheek instructs that one by the Lord’s punishment in the discipline of patience. No one who is chastened and corrected need lose hope, for one who loves his son chastises him. No one should despair of a remedy.

The Lord certainly would not exhort to repentance unless he promised pardon to the penitent. In the Gospel the Lord says, Just so, I tell you, there will be joy in heaven over one sinner who repents, more than over ninety-nine just who have no need of repentance.^[1] Since it is written, God is not the author of death, nor does he rejoice in the destruction of the living,^[2] certainly he, who wishes no one to perish, desires sinners to do penance and to return to life again through penance.^[3] And there, through Joel the prophet, he cries out and says, And now says the Lord, your God, return to me with your whole heart, at the same time with fasting, and weeping and mourning; and rend your hearts and not your garments, and return to the Lord, your God. For gracious and merciful is he, slow to anger, rich in kindness, and he softens the sentence inflicted against malice.^[4] In the Psalms we read also of the censure and of the clemency of God, at the same time, threatening and sparing, punishing that he may correct and saving when he has corrected. I will visit, he says, their crime with a rod and their guilt with stripes. Yet my kindness I will not take from them.

But the rest of this psalm runs thus: Where are Thine ancient compassions, Lord, which Thou swarest unto David in Thy truth? Remember, Lord, the reproach of Thy servants, which I have borne in my bosom of many nations; wherewith Thine enemies have reproached, O Lord, wherewith they have reproached the change of Thy Christ.^[1] Now it may with very good reason be asked whether this is spoken in the person of those Israelites who desired that the promise made to David might be fulfilled to them; or rather of the Christians, who are Israelites not after the flesh but after the Spirit. This certainly was spoken or written in the time of Ethan, from whose name this psalm gets its title, and that was the same as the time of David’s reign; and therefore it would not have been said, Where are Thine ancient compassions, Lord, which Thou hast sworn unto David in Thy truth? unless the prophet had assumed the person of those who should come long afterwards, to whom that time when these things were promised to David was ancient.