Humility is the only virtue that no devil can imitate. If pride made demons out of angels, there is no doubt that humility could make angels out of demons.
John ClimacusRemembrance 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)
John ClimacusBecome aware of God, in whose presence you are while you pray . . . Then take a formula of prayer and recite it with perfect attention both to the words you are saying and to the Person to whom you are saying them.
John ClimacusA characteristic of those who are still progressing in blessed mourning is temperance and silence of the lips; and of those who have made progress - freedom from anger and patient endurance of injuries; and of the perfect - humility, thirst for dishonors, voluntary craving for involuntary afflictions, non- condemnation of sinners, compassion even beyond one's strength. The first are acceptable, the second laudable; but blessed are those who hunger for hardship and thirst for dishonor, for they shall be filled with the food whereof there can be no satiety.
John ClimacusWhen the soul betrays itself and loses the blessed and longed-for fervor, let it carefully investigate the reason for losing it. And let it arm itself with all its longing and zeal against whatever caused this. For the former fervor can return only through the same door through which it was lost.
John ClimacusOur inhuman enemy inspires the thought that God loves mankind, and that He quickly forgives this sin. But when we observe the guile of demons, then we see that after the commission of the sin, they suggest to us that God is a righteous and implacable Judge. The first they say in order to lead us to sin, the second, in order to weigh us down in despair.
John Climacus