Fasting is an exceptional virtue; it represses bodily impulses and gives strength to the soul to fight against the poisoning of the heart through the senses, and provides it with a remedy against any past poisoning. Fasting causes the mind to be cleansed constantly. It withers up every evil thought and brings healthy, godly thoughts -- -holy thoughts that enlighten the mind and kindle it with more zeal and spiritual fervor.
When you fast and are nourished with abstinence, do not store the leftovers for tomorrow, but, as the Lord became poor and enriched us, feed someone who does not want to be hungry, you who hungers willingly. Then your fast will be like the dove who brings and joyfully proclaims salvation to your soul from the flood.
Fasting is absolutely indispensable for man. From the external aspect, it is a struggle of filial obedience to God, Who has given us the rules of fasting through His Holy Spirit. From the inner aspect, fasting is a struggle of restraint and self-limitation. In this lies the great value and sense of fasting, since a strict observance of fasts tempers one's will and perfects the character of one who is firm in his religious convictions and actions. Let us not forget that Christ Himself fasted, and foretold that His apostles would also fast.
The old man (Abba Moses) was asked, 'What is the good of the fasts and watchings which a man imposes on himself?' and he replied, 'They make the soul humble. For it is written, ‘Consider my affliction and my trouble, and forgive all my sins’ (Psalm 25:18). So if the soul gives itself all this hardship, God will have mercy on it.'
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.
Sear your loins by abstaining from food, and prove your heart by controlling your speech, and you will succeed in bringing the desiring and incensive powers of your soul into the service of what is noble and good.
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.
Beware of limiting the good of fasting to mere abstinence from meats. Real fasting is alienation from evil. ‘Loose the bands of wickedness.’ For give your neighbor the mischief he has done you. Forgive him his trespasses against you. Do not ‘fast for strife and debate.’ You do not devour flesh, but you devour your brother. You abstain from wine, but you indulge in outrages. You wait for evening before you take food, but you spend the day in the law courts. Woe to those who are ‘drunken, but not with wine.’ Anger is the intoxication of the soul, and makes it out of its wits like wine.
Unless curbed by the fear of God that accompanies the practice of the virtues, spiritual knowledge leads to vanity; for it encourages the person puffed up by it to regard as his own what has merely been lent to him, and to use his borrowed intelligence to win praise for himself. But when his practice of the virtues increases concomitantly with his longing for God, and he does not arrogate to himself more spiritual knowledge than is needed for the task in hand, then he is made humble, reduced to himself by principles which are beyond his capacity.
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).
Almsgiving heals the soul's incensive power; fasting withers sensual desire; prayer purifies the intellect and prepares it for contemplation of created beings. For the Lord has given us commandments which correspond to the powers of the soul.
Suppose you have ordered yourself not to eat fish; you will find that the enemy continually makes you long to eat it. You are filled with an uncontrollable desire for the thing that is forbidden. In this way you can see how Adam's fall typifies what happens to all of us. Because he was told not to eat from a particular tree, he felt irresistibly attracted to the one thing that was forbidden him.
Fear God and keep His commandments both in your feelings and in your intellect. If you force yourself to keep them in your intellect, bit by bit you will attain to fulfilling them in your feelings.
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...
In no art do the artists judge the result of their work by the tools they use, but they await the work's completion and by it judge the art. Adopting such a practice with regard to food, not placing all your hope on fasting, but fasting moderately and according to the amount of your strength, strive toward mental activity. In this way you can avoid pride and will not spurn God's good works, sending up praises to God for everything.