Watchfulness and the Jesus Prayer, as I have said, mutually reinforce each other, for close attentiveness goes with constant prayer, while prayer goes with close watchfulness and attentiveness of intellect.
Keep your mind from malicious thoughts of your neighbors, knowing that such thoughts are hurled by diabolical power, to keep your mind from your own sins and from seeking.
Baptism does not take away our free will or freedom of choice, but gives us the freedom no longer to be tyrannized by the devil unless we choose to be. After baptism it is in our power either to persist willingly in the practice of the commandments of Christ, into whom we were baptized, and to advance in the path of His ordinances, or to deviate from this straight way and fall again into the hands of our enemy...
Take care never to receive Communion while you have anything against anyone, even if this is only a hostile thought. Not until you have brought about reconciliation through repentance should you communicate, [receive the Mysteries]. But you will learn this, too, through prayer.
The heart which is constantly guarded, and is not allowed to receive the forms, images and fantasies of the dark and evil spirits, is conditioned by nature to give birth from within itself to thoughts filled with light. For just as coal engenders a flame, or a flame lights a candle, so will God, who from our baptism dwells in our heart, kindle our mind to contemplation when He finds it free from the winds of evil and protected by the guarding of the intellect.
We should look upon every believer alike, and suppose that Christ abides in each; we must have such loving disposition towards him as to be ready to lay down our life for him. We should never think or say that someone is evil, but, as is said, should see everyone as good. If you see someone attacked by the passions, hate not the brother but the passions attacking him.
Anger is by nature designed for waging war with the demons and for struggling with every kind of sinful pleasure. Therefore angels, arousing spiritual pleasure in us and giving us to taste its blessedness, incline us to direct our anger against the demons. But the demons, enticing us towards worldly lusts, make us use anger to fight with men, which is against nature, so that the mind, thus stupefied and darkened, should become a traitor to virtues.
As a blacksmith can do nothing without the help of fire, however skilled he may be in wielding his tools, so a man should do everything he can on his side to purify his heart, using virtues as tools for this purpose; but without fire of the Spirit, everything he does will remain inactive and useless for his aim, for by itself what he does is powerless to cleanse the soul of its dirt and foulness.
We should look upon each believer alike, and suppose that Christ abides in each; we must have such loving disposition towards him as to be ready to lay down our life for him. We should never think or say that someone is evil, but, as is said, should see everyone as good. If you see someone attacked by passions, hate not the brother but the passions attacking him. And when you see someone succumbing to the tyranny of lusts and bad habits, have a still greater compassion for him, lest you suffer a similar temptation - since you are changeable and under the influence of changeable matter.
Fasting, while of value in itself, is not something to boast of in front of God, for it is simply a tool for training those who desire self-restraint. The ascetic should not feel proud because he fasts; no artist ever boasts that his accomplishment is simply due to his tools; but he waits for the work itself to give proof of his skill.
As earth thrown over it extinguishes a fire burning in a stove, so worldly cares and every kind of attachment to something, however small and insignificant, destroys the warmth of the heart which was there at first.
Those pursuing the spiritual way should train themselves to hate all uncontrolled desires until this hatred becomes habitual. With regard to self-control in eating, we must never feel loathing for any kind of food, for to do so is abominable and utterly demonic. It is emphatically not because any kind of food is bad in itself that we refrain from it. But by not eating too much or too richly we can to some extent keep in check the excitable parts of our body. In addition we can give to the poor what remains over, for this is the mark of sincere love.
When the enemy tempts you with thoughts of faithlessness, with all your heart say, I believe completely whatever the Church believes, whatever Christ says in the Holy Gospels, whatever the Holy Apostles and the Holy Fathers said. 'I don't, however, believe you, devil, for you are a liar and a thief.'
No man, wise in his own opinion, because he has studied all the sciences and is learned in external wisdom, will ever penetrate God's mysteries or see them unless he first humbles himself and becomes foolish in his heart, repudiating his self-opinion together with his acquirements of learning. For a man who acts thus and follows with undaunted faith those who are wise in things Divine, is guided by them and with them enters into the city of the living God, and, taught and enlightened by the Holy Spirit, sees and knows things which no one else can see or know. Thus he becomes taught of God.
The old man was asked, 'What is the good of the fasts and watchings which a man imposes on himself?' and he replied, 'They make the soul humble. For it is written, Consider my affliction and my trouble, and forgive all my sins' (Psalm 25:18). 'So if the soul gives itself all this hardship, God will have mercy on it.' The old man was (also) asked, 'What should a man do in all the temptations and evil thoughts that come upon him?' The old man said to him, 'He should weep and implore the goodness of God to come to his aid, and he will obtain peace if he prays with discernment. For it is written, 'With the Lord on my side I do not fear. What can man do to me?' (Psalm 118:6).