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.
Fasts and vigils, the study of Scripture, renouncing possessions and everything worldly are not in themselves perfection, as we have said; they are its tools. For perfection is not to be found in them; it is acquired through them. It is useless, therefore, to boast of our fasting, vigils, poverty, and reading of Scripture when we have not achieved the love of God and our fellow men. Whoever has achieved love has God within himself and his intellect is always with God.
My brother, the passions are afflictions; and so the Lord does not excommunicate us because of them, but He says: 'Call upon me in the time of affliction; and I will deliver thee, and thou shalt glorify me'. Therefore, when beset by any kind of passion, there is nothing more useful than to call upon the Name of God. All we can do, weak as we are, is to flee for refuge to the Name of Jesus. For the passions, being demons, retreat if this Name is invoked.
I shall speak first about control of the stomach, the opposite to gluttony, and about how to fast and what and how much to eat. I shall say nothing on my own account, but only what I have received from the Holy Fathers. They have not given us only a single rule for fasting or a single standard and measure for eating, because not everyone has the same strength; age, illness or delicacy of body create differences. But they have given us all a single goal: to avoid over-eating and the filling of our bellies... A clear rule for self-control handed down by the Fathers is this: stop eating while still hungry and do not continue until you are satisfied.
The enemy is within ourselves. An invisible war is taking place within us. If interior evil is defeated, then the external, weaker, foe will surrender.
If we remember the thief who, for a single confession on the cross, was taken into Paradise, we shall realize that it was not for the merit of the life he lived that he obtained so great blessedness, but that it was his by the gift of God, Who had mercy on him. Or, let us think of David, the king, whose two grievous and awful crimes were wiped away by one word of penitence. Neither here do we see that the merit of what he did was equal to obtaining pardon for such great offense, but the grace of God did the more abound when on the occasion of true penitence He did away with all that weight of sin for one single word of genuine confession. Again, when we consider the beginnings of man's calling and salvation, which, as the Apostle tells us, is not of ourselves or of our words, but we are saved by the gift and grace of God, we shall be able clearly to perceive how the end of perfection is not 'of him that willeth, nor of him that runneth, but of God Who showeth mercy,' Who makes us victors over our vices, although we have no merit at all of life or labors to weigh against them, nor does the effort of our will avail for us to reach the steep summit of righteousness, or to subdue the flesh which we are bound to use... For the outcome of all good flows from His grace, Who hath bestowed so great an eternity of bliss and such immeasurable glory, with manifold generosity, upon the weak will and the short life-work of man.
But a sober and prudent man who desires to be saved, when he sees from what it is that he suffers harm, carefully preserves himself from evil remembrances, is not drawn into passionate thoughts, avoids meetings and conversations with those for whom he feels attraction and avoids every occasion for sin, fearing lest he himself ignite a fire within himself. This is the warfare which proceeds from one’s own lust, which a man brings on himself
If you wish to be delivered from shameful passions, do not behave with anyone familiarly, especially with those toward whom your heart is inclined by a lustful passion; through this you will be delivered also from vainglory. For in vainglory is involved the pleasing of men, in the pleasing of men is involved familiarity of behavior, and familiarity of behavior is the mother of all passions.
Monastic life is called the art of arts and the science of sciences; for it does not bring perishable blessings akin to the things of this world, which drive the mind from what is best and engulf it; but monk hood promises us wonderful and unspeakable treasures which the ' Eye that not seen, nor ear heard, neither have entered into the heart of man' (1 Cor. ii. 9). Hence, ' we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world' (Ephes. vi. 12). If therefore present existence is but darkness, let us flee from it, let us flee by returning our mind and our heart. Let us have nothing in common with the enemy of God, for 'whosoever will be a friend of the world is the enemy of God' ( James iv. 4). And who can help the enemy of God ? Therefore let us imitate our fathers and, like them, let us seek the treasure existing within our hearts and, having found it, let us hold fast to it in doing and guarding - for which task we were destined from the beginning.
It is, indeed, impossible for the mind not to be troubled by thoughts, but accepting them or rejecting them is possible for everyone who makes an effort...therefore we practice the frequent reading of Scripture, so that we may be open to a spiritual point of view. For this reason we frequently chant the psalms, so that we may continually grow in compunction. For this reason we are diligent in vigils, fasting, and praying, so that the mind which has been stretched to its limits may not taste earthly things but contemplate heavenly ones. When these things cease because negligence has crept in again, then, it is inevitable that the mind, by the accumulated filth of the vices, will soon turn in a carnal direction and fall.
The man who does not humble himself and does not cleanse his heart from evil desires fasts in vain. He may eat nothing at all, but it will be to no avail if there is evil inside him. He must first cleanse himself from the evil within in order to receive the Lord.
Let us have recourse to humility on all occasions; for the humble lie prone on the ground, and how can a man fall if he lies on the ground? But a man who stands on a height can easily fall.
Temptations are sent for improvement when God delivers his righteous ones to various temptations, humiliating them for some slight and unimportant offense, or to increase their purity, in order that every uncleanliness of thought, or... dross which He sees they have harbored in secret, may be burnt away in this present life, and that so He may bring them, as it were pure gold, to the future judgment...
When Christ Himself spoke to Paul and called him, He could have opened his eyes at once and made known to him the way of perfection; instead He sent him to Ananias and told him to learn from him the way of truth, saying: 'Arise and go into the city, and there you will be told what you must do' (Acts 9:6). In this manner He teaches us to be guided by those who are advanced on the way, so that the vision rightly given to Paul should not be wrongly interpreted; otherwise it might lead later generations presumptuously to suppose that each individual must be initiated into truth directly by God, as Paul was, and not by the fathers.
