Poison in your heart: the memory of insults
The memory of insults is the residue of anger. It keeps sins alive, hates justice, ruins virtue, poisons the heart, rots the mind, defeats concentration, paralyzes prayer, puts love at a distance, and is a nail driven into the soul.
If anyone has appeased his anger, he has already suppressed the memory of insults, while as long as the mother is alive the son persists. In order to appease the anger, love is necessary.
Remembrance of Jesus’ passion will heal your soul of resentment, by making it ashamed of itself when it remembers the patience of the Lord.
Some people have wearied themselves and suffered for a long time in order to extract forgiveness. By far the best course, however, is to forget the offences, since the Lord says: "Forgive at once and you will be forgiven in generous measure" cf. Luke 6:37-38.
Forgetting offences is a sign of sincere repentance. If you keep the memory of them, you may believe you have repented but you are like someone running in his sleep.
Let no one consider it a minor defect, this darkness that often clouds the eyes even of spiritual people.
St. John Climacus
Ladder of Divine Ascent