For not only are spiritual riches and heavenly gifts received from God, but earthly and material possessions also proceed from His bounty, that He may be justified in requiring an account of those things which He has not so much put in our possession, as committed to our stewardship. God’s gifts, therefore, we must use properly and wisely, lest the material for good work should become an occasion for sin.
He who is afraid of God's punishment has a slave-like fear of God, and it is this that makes him refrain from evil: 'Out of fear of the Lord men shun evil' (Prov. 16:6. LXX)... through fear of what threatens us we sinners may be led to repent and may seek deliverance from our sins...The more a man struggles to do good, the more fear grows in him, until it shows him his slightest faults, those which he thought of as nothing while he was still in the darkness of ignorance. When fear in this way has become perfect, he himself becomes perfect through inward grief: he no longer desires to sin but, fearing the return of the passions, he remains in this pure fear invulnerable. As the psalm puts it, 'The fear of the Lord is pure, and endures for ever' (Ps. 19:9. LXX). The first kind of fear is not pure, for it arises in us because of our sins. But, independent of sin, the person who has been purified continues to feel fear, not because he sins, but because, being human, he is changeable and prone to evil. In his humility, the further he advances through the acquisition of the virtues, the more he fears. This is natural; for everyone who possesses wealth greatly fears loss, punishment, dishonor, and the consequent fall from his high estate...The sign of the first kind of fear is hatred of sin and anger towards it, like someone wounded by a wild beast. The sign of perfect fear is the love of virtue and the fear of relapsing, since no one is unalterable.
For forgiveness of sins is most efficaciously prayed for with almsgiving and fasting, and supplications that are winged by such aids mount swiftly to God’s ears; since it is written, 'the merciful man doeth good to his own soul' (Prov. xi. 17), and nothing is so much a man’s own as that which he spends on his neighbor. For that part of his material possessions with which he ministers to the needy, is transformed into eternal riches, and such wealth is begotten of this bountifulness as can never be diminished or in any way destroyed, for 'blessed are the merciful, for God shall have mercy on them' (Matt. v.7), and He himself shall be their chief Reward, who is the Model of His own command.
Our holy fathers have renounced all other spiritual work and concentrated wholly on this one doing, that is, on guarding the heart, convinced that, through this practice, they would easily attain every other virtue, whereas without it not a single virtue can be firmly established.
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.
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.