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.
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.
To act 'according to one’s strength' means to use a little less than necessary both of food, and drink, and sleep... As for food, restrain yourself when you wish to eat a little more, and in this way you will always make use of it moderately.
He who chooses maltreatment and dishonor for the sake of truth is walking on the apostolic path; he has taken up the cross and is bound in chains (cf. Mt 16:24). But when he tries to concentrate his attention on the heart without accepting these two, his intellect wanders from the path and he falls into the temptations and snares of the devil.
If you wish to be saved and 'to come unto the knowledge of the truth' (I Tim. 2:4), endeavor always to transcend sensible things, and through hope alone to cleave to God. Then you will find principalities and powers fighting against you (Eph. 6:12), deflecting you against your will and provoking you to sin. But if you prevail over them through prayer and maintain your hope, you will receive God's grace, and this will deliver you...
I think it best that a man should have a little bit of all the virtues. Therefore, get up early every day and acquire the beginning of every virtue and every commandment of God. Use great patience, with fear and long-suffering, in the love of God, with all the fervor of your soul and body. Exercise great humility, bear with interior distress; be vigilant and pray often with reverence and groaning, with purity of speech and control of your eyes. When you are despised do not get angry; be at peace, and do not render evil for evil. Do not pay attention to the faults of others, and do not try to compare yourself with others, knowing you are less than every created thing. Renounce everything material and that which is of the flesh. Live by the cross, in warfare, in poverty of spirit, in voluntary spiritual asceticism, in fasting, penitence and tears, in discernment, in purity of soul, taking hold of that which is good. Do your work in peace. Persevere in keeping vigil, in hunger and thirst, in cold and nakedness, and in sufferings. Shut yourself in a tomb as though you were already dead, so that at all times you will think death is near.
A haughty person is not aware of his faults, or a humble person of his good qualities. An evil ignorance blinds the first, an ignorance pleasing to God blinds the second.
He who wants to cross the spiritual sea is long-suffering, humble, vigilant and self-controlled. If he impetuously embarks on it without these four virtues, he agitates his heart, but cannot cross.
Concerning fasting, do not grieve, as I have said to you before: God does not demand of anyone labors beyond his strength. And indeed, what is fasting if not a punishment of the body in order to humble a healthy body and make it infirm for passions, according to the word of the Apostle: 'When I am weak, then am I strong' (II Corinthians 12:10).
