Joel 2:13

Let each one confess his sin, I beseech you, brethren, while he who has sinned is still in this world, while his confession can be admitted, while the satisfaction and remission effected through the priest is pleasing with the Lord. Let us turn to the Lord with our whole mind, and, expressing repentance for our sin with true grief, let us implore God's mercy. Let the soul prostrate itself before him; let sorrow give satisfaction to him; let our every hope rest upon him. He himself tells how we ought to ask. He says, "Return to me with all your hearts, in fasting and in weeping, and in mourning, and rend your hearts, not your garments." Let us return to the Lord with a whole heart; let us placate his wrath and displeasure by fastings, weepings and mournings, as he himself admonishes.

How well does the holy prophet teach that the seeds of good works must be watered by a river of tears! No seeds germinate unless they are watered; nor does fruit come forth from the seed if deprived of the aid of water. Accordingly, we too, if we wish to keep the fruits of our seeds, let us not stop watering our seeds with tears that must be poured out more from the heart than from the body. Therefore it is said to us through the prophet that we rend "our hearts and not our garments," something we can do when we recall that we ourselves, even if not in deed, frequently sin at least in thought. Because the "earthly tent burdens the thoughtful mind" and our land does not cease to produce thorns and thistles for us. We are unable to get to eating our bread, unless we will have been worn out by weariness and the sweat of our brow.

"Rend your hearts, not your garments," that is, have recourse to thoughts of compunction, soften the obduracy of your thinking, accept beneficial advice, abandon the way of vice and travel by that way which leads directly to God. After all, many are the founts of compassion and mercy that flow from him, and in his exercise of longsuffering he is not in the custom of putting his threats into effect. In fact, he indicated as much by saying "repenting of the troubles," that is, by instilling dread by the threats of punishment, and by the changes in human beings for the better transforming the threats into something pleasant. The God of all, you see, does not intend one thing at one time and another thing at another, or like us repent of what he does. Rather, while making threats he has mercy within himself, and he offers it to those who are sorry for their sins, and while making promises of good things he knows those who are good and those who are unworthy of his gifts, extending them to the former and giving to the latter the opposite of what he promises.