12 Now do thou consider in how much more unfeeling and insensible in a way you have acted even than he, praying against your enemies. He did not beg his master to demand, but he himself demanded, the hundred pence; whereas thou even callest on the Master for this shameless and forbidden demand. And he seized his fellow-servant's throat not before his lord's eyes, but outside; while thou in the very moment of prayer, standing in the King's presence, doest this. And if he, for doing this without either having urged his master to the demand, and after going forth, met with no forgiveness; thou, both stirring up the Master to (exacting) this forbidden payment, and doing this before his eyes, what sort of penalty will thou have to pay?
Tell me. But your mind is inflamed by the memory of the enmity, and swells, and your heart rises, and when recurring in memory to him who has caused pain, you are unable to reduce the swelling of your thought. But set against this inflammation the memory resulting from your own sins committed the fear resulting from the punishment to come. Recall to memory for how many things you are accountable to your master, and that for all those things you owe Him satisfaction; and this fear will surely overcome that anger; since indeed this is far more powerful than that passion.
Recall the memory of hell and punishment and vengeance during the time of your prayer; and you will not be able even to receive your enemy into your mind. Make your mind contrite, humble your soul by the memory of the offenses committed by you, and wrath will not be able even to trouble you. But the cause of all these evils is this, that we scrutinise the sins of all others with great exactitude; while we let our own pass with great remissness. Whereas we ought to do the contrary— to keep our own faults unforgotten; but never even to admit a thought of those of others.
If we do this we shall both have God propitious, and shall cease cherishing immortal anger against our neighbours, and we shall never have any one as an enemy; and even if we should have at any time we shall both quickly put an end to his enmity, and should obtain speedy pardon for our own sins. For just as he who treasures up the memory of wrong against his neighbour does not permit the punishment upon his own sins to be done away; so he who is clear of anger will speedily be clear of sins also.
For if we, wicked as we are and enslaved to passion, on account of the commandment of God overlook all the faults committed against us, much more will He who is a lover of mankind, and good, and free from any passion, overlook our delinquencies, rendering to us the recompense of our kindly spirit towards our neighbour in the forgiveness of our own sins: which God grant that we may attain, by the grace and lovingkindness of our Lord Jesus Christ, to whom is the glory and the dominion, to the ages of the ages. Amen.
Source: Homily Against Publishing the Errors of the Brethren (New Advent)