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.
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.
Such are the souls of the saints: they love their enemies more than themselves, and in this age and in the age to come they put their neighbor first in all things, even though because of his ill-will he may be their enemy.
If we want to do something but cannot, then before God, Who knows our hearts, it is as if we have done it. This is true whether the intended action is good or bad.
If a man has some spiritual gift and feels compassion for those who do not have it, he preserves the gift because of his compassion. But a boastful man will lose it through succumbing to the temptations of boastfulness.
Not every man can be trusted when giving advice to those who seek it. We can trust only him who has received from God the grace of discrimination and who ... has acquired through great humility and long practice of the virtues an intellect blessed with spiritual insight. Such a man is in a position to advise, not everyone, but at least those who seek him out voluntarily and who question him by their own choice; for he has learned things in their true order.
If you fast regularly, do not be inflated with pride; if you think highly of yourself because of it, then you had better eat meat. It is better for a man to eat meat than to be inflated with pride and glorify himself.
If we desire to acquire faith the foundation of all blessings, the door to God's mysteries, unflagging defeat of our enemies, the most necessary of all the virtues, the wings of prayer and the dwelling of God within the soul--we must endure every trial imposed by our enemies and by our many and various thoughts... if we forcibly triumph over the trials and temptations that befall us, it will not be we who are victorious, but Christ, Who is present in us through faith.
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.
It is always possible to make a new start by means of repentance. 'You fell,' it is written, 'now arise'(cf. Prov. 24:16). And if you fall again, then rise again, without despairing at all of your salvation, no matter what happens. So long as you do not surrender yourself willingly to the enemy, your patient endurance, combined with self-reproach, will suffice for your salvation. 'For at one time we ourselves went astray in our folly and disobedience,' says St. Paul. '... Yet He saved us, not because of any good things we had done, but in His mercy' (Tit. 3:3,5).