This is the mark of Christianity--however much a man toils, and however many righteousnesses he performs, to feel that he has done nothing, and in fasting to say, 'This is not fasting,' and in praying, 'This is not prayer,' and in perseverance at prayer, 'I have shown no perseverance; I am only just beginning to practice and to take pains;' and even if he is righteous before God, he should say, 'I am not righteous, not I; I do not take pains, but only make a beginning every day.'
For this world is opposed to the world above, and this present age to the eternity above. The Christian therefore, according to Holy Scripture, must deny the world, and be translated and pass in mind out of this present age, in which the mind is placed and exposed to allurements ever since the transgression of Adam, into another age, and in frame of thought must live in the world of the Godhead above, as it is said, But our conversation is in heaven. (Phil. iii. 20.).
Therefore we must not grow weary. We must be steadfast, immovable, always abounding in the work of the Lord, knowing that in the Lord our labor is not in vain (I Corinthians 15:58). Having once begun, we must not cease to perform deeds worthy of our repentance. To rest is the same as to retreat.
What can God do with one who willfully gives himself over to the world, and is deceived by its pleasures, or led astray by material wanderings? The man to whom He gives help is the one who turns away from material pleasures and from his former habits, who drags his mind at all times to the Lord, whether it will or not, who denies himself and seeks the Lord only. This is the man whom He keeps under His care: who guards himself on every side from the snares and entanglements of the material world, who works out his own salvation with fear and trembling, who passes with all heed amidst the snares and entanglements and lusts of this world, and seeks the help of the Lord, and hopes by His mercy to be saved through grace.
One should not ponder divine matters on a full stomach, say the ascetics. For the well-fed, even the most superficial secrets of the Trinity lie hidden.
The head of every good striving and the pinnacle of all corrections is to persevere in prayer, by which we may ever obtain, through entreaty of God, all the other virtues as well. By prayer those who are worthy partake of the sanctity of God and spiritual activity and the union of the mind with the Lord in unutterable love. He who constantly forces himself to endure in prayer is roused by spiritual love to Divine fervor and flaming desire towards God, and he receives, according to his measure, the grace of spiritual, sanctifying perfection.
Knowing the exact nature of everything, God permits each person to be tested according to his strength. As St. Paul puts it: 'God is to be trusted not to let you be tried beyond your strength, but with the trial He will provide a way out, so that you are able to bear it' (1 Cor. 10:13).
But, say the saints, now that you recognize the darkness in your own heart and the weakness of your flesh, you lose all desire to pass judgment on your neighbor. Out of your own darkness you see the heavenly light that shines in all created things reflected the clearer: you cannot detect the sins of others while your own are so great. For it is in your eager striving for perfection that you first perceive your own imperfection. And only when you have seen your imperfection, can you be perfected. Thus perfection proceeds out of weakness.