The Lord commands all men to repent (Matt. 4:17), so that even the spiritual and those making progress should not neglect this injunction and fail to give attention to the smallest and most subtle errors.
We ought to learn the virtues through practicing them, not merely through talking about them, so that by acquiring the habit of them we do not forget what is of benefit to us. 'The kingdom of God,' St. Paul says, 'resides not in words but in power' (I Cor. 4:20). For he who tries to discover things through actual practice will come to understand what gain or loss lies in any activity that he pursues.
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.
St. John Climacus was asked if there are reliable signs by which it's possible to know whether a soul is drawing near to God or moving away from Him. After all, regarding ordinary things there are clear signs as to whether they're good or not. When, for instance, cabbage, meat or fish begins to rot, it's easy to notice it, since the rotting object begins to give off a foul odor, the color and taste change, and its external appearance witnesses to its deterioration. Well, and what about the soul? After all, it's bodiless and can't give off a bad smell or change its appearance. To this question the Holy Father replies, 'A sure sign of the deadening of the soul is the avoidance of church services.'
There is a sin which is always 'unto death' [1 Jn 5:16]; the sin which we have not repented. Even a saint's prayers will not be heard for the unrepented sin. The person who repents correctly does not imagine that his sins are cancelled through his own effort; but knows that through this effort he makes peace with God.
When God is thanked, He gives us still further blessings, while we, by receiving His gifts, love Him all the more and through this love attain that divine wisdom whose beginning is the fear of God (cf. Prov. 1:7).
When you close the doors to your dwelling and are alone you should know that there is present with you the angel whom God has appointed for each man...This angel, who is sleepless and cannot be deceived, is always present with you; he sees all things and is not hindered by darkness. You should know, too, that with him is God, who is in every place; for there is no place and nothing material in which God is not, since He is greater than all things and holds all men in His hand.
We ought all of us always to give thanks to God for both the universal and the particular gifts of soul and body that He bestows on us. The universal gifts consist of the four elements and all that comes into being through them, as well as all the marvelous works of God mentioned in the divine Scriptures. The particular gifts consist of all that God has given to each individual. These include wealth, so that one can perform acts of charity; poverty, so that one can endure it with patience and gratitude; authority, so that one can exercise right judgment and establish virtue; obedience and service, so that one can more readily attain salvation of soul; health, so that one can assist those in need and undertake work worthy of God; sickness, so that one may earn the crown of patience; spiritual knowledge and strength, so that one may acquire virtue; weakness and ignorance, so that, turning one's back on worldly things, one may be under obedience in stillness and humility; unsought loss of goods and possessions, so that one may deliberately seek to be saved and may be helped when incapable of shedding all one's possessions or even of giving alms; ease and prosperity, so that one may voluntarily struggle and suffer to attain the virtues and thus become dispassionate and fit to save other souls; trials and hardship so that those who cannot eradicate their own will may be saved in spite of themselves, and those capable of joyful endurance may attain perfection.
He who reveres the Lord does what is commanded, and if he commits some sin or disobeys Him, endures whatever he has to suffer for this as being his desert.