The right practice of abstinence is needful not only to the mortification of the flesh but also to the purification of the mind. For the mind then only keeps holy and spiritual fast when it rejects the food of error and the poison of falsehood.
The spiritual discipline of fasting is a tool for shifting the focus away from us and toward the Lord and our brothers and sisters in whom we encounter Him each day. If we distort fasting into a private religious accomplishment to prove how holy we are, we would do better not to fast at all. That would simply be a way of serving ourselves instead of God and those who bear His image and likeness. In Lent, our focus must be set squarely on Christ and His living icons, not on us. The fundamental calling of the Christian life is to become like our Lord, Who offered Himself up for the salvation of the world purely out of love. If we are truly in communion with Him, then we too must offer up ourselves for our neighbors. And as He taught in the parable of the Good Samaritan, there are no limits on what it means to be a neighbor to anyone who is in need, regardless of nationality, culture, or anything else. Those who limit their concern for people according to such standards place serving the kingdoms of this world before fidelity to the Kingdom of God.
The enemy of our salvation especially strives to draw our heart and mind away from God when we are about to serve Him, and endeavors to adulterously attach our heart to something irrelevant. Be always, every moment, with God, especially when you pray to Him. If you are inconstant, you will fall away from life, and will cast yourself into sorrow and straitness.
The body is a slave, the soul a sovereign, and therefore it is due to Divine mercy when the body is worn out by illness: for thereby the passions are weakened, and a man comes to himself; indeed, bodily illness itself is sometimes caused by the passions.
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.
Fasting appears gloomy until one steps into its arena. But begin and you will see what light it brings after darkness, what freedom from bonds, what release after a burdensome life…
We are told: It is no big deal to eat non-Lenten food during Lent. It is no big deal if you wear expensive beautiful outfits, go to the theater, to parties, to masquerade balls, use beautiful expensive china, furniture, expensive carriages and dashing steeds, amass and hoard things, etc. Yet what is it that turns our heart away from God, away from the Fountain of Life? Because of what do we lose eternal life? Is it not because of gluttony, of expensive clothing like that of the rich man of the Gospel story, is it not because of theaters and masquerades? What turns us hard-hearted toward the poor and even toward our relatives? Is it not our passion for sweets, for satisfying the belly in general, for clothing, for expensive dishes, furniture, carriages, for money and other things? Is it possible to serve God and mammon, to be a friend to the world and a friend to God, to serve Christ and Belial? That is impossible. Why did Adam and Eve lose paradise, why did they fall into sin and death? Was it not because of one evil? Let us attentively consider why we do not care about the salvation of our soul, which cost the Son of God so dearly. Why do we compound sin upon sin, fall endlessly into opposing to God, into a life of vanity? Is it not because of a passion for earthly things and especially for earthly pleasures? What makes our hearts become crude? Why do we become flesh and not spirit, perverting our moral nature? Is it not because of a passion for food, drink, and other earthly comforts? How after this can one say that it does not matter whether you eat non-Lenten food during Lent? The fact that we talk this way is in fact pride, idle thought, disobedience, refusal to submit to God, and separation from Him.
Those pursuing the spiritual way should train themselves to hate all uncontrolled desires until this hatred becomes habitual. With regard to self-control in eating, we must never feel loathing for any kind of food, for to do so is abominable and utterly demonic. It is emphatically not because any kind of food is bad in itself that we refrain from it. But by not eating too much or too richly we can to some extent keep in check the excitable parts of our body. In addition we can give to the poor what remains over, for this is the mark of sincere love.
The partaking of food has three degrees: abstinence, adequacy and satiety. To abstain, means to remain a little hungry after eating; to eat adequately, means neither to be hungry, nor weighed down. But eating beyond satiety is the door to belly-madness, through which lust comes in. But you, firm in knowledge, choose what is best for you, according to your powers, without overstepping the limits...
I have said these things, not that we may disparage fasting, but that we may honor fasting; for the honor of fasting consists not in abstinence from food, but in withdrawing from sinful practices; since he who limits his fasting only to an abstinence from meats, is one who especially disparages it. Dost thou fast? Give me proof of it by thy works! Is it said by what kind of works? If thou seest a poor man, take pity on him! If thou seest an enemy, be reconciled to him! If thou seest a friend gaining honor, envy him not! If thou seest a handsome woman, pass her by! For let not the mouth only fast, but also the eye, and ear, and the feet, and the hands, and all the members of our bodies. Let the hands fast, by being pure from rapine and avarice. Let the feet fast, by ceasing from running to the unlawful spectacles. Let the eyes fast, being taught never to fix themselves rudely upon handsome countenances, or to busy themselves with strange beauties. For looking is the food of the eyes, but if this be such as is unlawful or forbidden, it mars the fast; and upsets the whole safety of the soul; but if it be lawful and safe, it adorns fasting. For it would be among things the most absurd to abstain from lawful food because of the fast, but with the eyes to touch even what is forbidden. Dost thou not eat flesh? Feed not upon lasciviousness by means of the eyes. Let the ear fast also. The fasting of the ear consists in refusing to receive evil speakings and calumnies. 'Thou shalt not receive a false report,' it says.
Fasting was of no benefit to that Pharisee in the Gospel, even though he always fasted two days a week, because he had adulterated it with pride and condemnation of his neighbor (Luke 18:11-12). Not that this means fasting is unprofitable. Moses, Elijah & the Lord Himself showed how beneficial it is for those who fast properly in a way pleasing to God.
According to St. Gregory the Sinaite there are three degrees in eating: temperance, sufficiency, and satiety. Temperance is when someone wants to eat some more food but abstains, rising from the table still somewhat hungry. Sufficiency is when someone eats what is needed and sufficient for normal nourishment. Satiety is when someone eats more than enough and is more than satisfied. Now if you cannot keep the first two degrees and you proceed to the third, then, at least, do not become a glutton, remembering the words of the lord: 'Woe unto you that are full now, for you shall hunger' (Lk. 6:25). Remember also that rich man who ate in this present life sumptuously every day, but who was deprived of the desired bosom of Abraham in the next life, simply because of this sumptuous eating.
Fasting is beneficial when it is undertaken for quelling desire, humbling the soul, transforming hatred, extinguishing anger, erasing remembrance of wrongs, and for the purity of the understanding and the practice of prayer.
Hold faith and humility fast within you; for through them you will find mercy, help, and words spoken by God in the heart, along with a protector who stands beside you both secretly and manifestly.
The undefiled beauty of fasting is the pure mother of character. It causes philosophy to gush forth, and offers a crown. It negotiates Paradise for us and grants a paternal family for those who fast. Of this Adam was deprived, and he attracted death, when he dishonored the worth of feasting. For at the time when it was treated scornfully, the God of all, the Creator and the Master was at once displeased. To those who honor it He grants eternal life.