Fasting was ordained in Paradise. The first injunction was delivered to Adam, ‘Of the tree of the knowledge of good and evil you shall not eat.’ ‘You shall not eat’ is a law of fasting and abstinence. The general argument is rather against excess than in support of ceremonial abstinence. In Paradise there was no wine, no butchery of beasts, no eating of flesh. Wine came in after the flood. Noah became drunk because wine was new to him. So fasting is older than drunkenness. Esau was defiled, and made his brother’s slave, for the sake of a single meal. It was fasting and prayer which gave Samuel to Hannah. Fasting brought forth Samson. Fasting begets prophets, strengthens strong men. Fasting makes lawgivers wise, is the soul’s safeguard, the body’s trusty comrade, the armor of the champion, the training of the athlete.
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
Even if thy soul should suffer somewhat from an offense, keep the sorrow within thyself. For it is said: 'Within me my heart is troubled' (Psalm 142:4), that is, the passion has not come out, but has been humbled like a wave that has broken up on the shore. Calm thy raging heart. Let thy passions be ashamed at the presence of reason in thee, as playful children are ashamed before a man commanding respect.
Confirm yourself in this truth: that every Divine writing that is in agreement with the path of salvation instructs, teaches, chastises, and strengthens, that our path might be ever according to God.
Of the beliefs and public doctrines entrusted to the care of the Church, there are some which are based on Scriptural teaching, others which we have received handed down in mystery by the tradition of the Apostles; and in relation to the true religion they both have the same force.
You have no peace from thoughts, which impel you to trouble others, and in turn to be troubled by others. But know, my brother, that if we offend by word or deed, we are thereby ourselves offended a hundredfold. Be longsuffering in all things and refrain from letting your own will enter into anything. Carefully examine your thoughts lest they infect your heart with deadly poison (ill temper) and make you take a gnat for a camel, a pebble for a cliff, and lest you become like a man who has a beam in his own eye but beholds the mote in the eye of another.
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.
We must strive after a quiet mind. As well might the eye ascertain an object put before it while it is wandering restless up and down and sideways, without fixing a steady gaze upon it, as a mind, distracted by a thousand worldly cares, be able clearly to apprehend the truth. He who is not yet yoked in the bonds of matrimony is harassed by frenzied cravings, and rebellious impulses, and hopeless attachments; he who has found his mate is encompassed with his own tumult of cares; if he is childless, there is desire for children; has he children? Anxiety about their education, attention to his wife, care of his house, oversight of his servants, misfortunes in trade, quarrels with his neighbors, lawsuits, the risks of the merchant, the toil of the farmer. Each day, as it comes, darkens the soul in its own way; and night after night takes up the day's anxieties, and cheats the mind with illusions in accordance. Now one way of escaping all this is separation from the whole world; that is, not bodily separation, but the severance of the soul's sympathy with the body, and to live so without city, home, goods, society, possessions, means of life, business, engagements, human learning, that the heart may readily receive every impress of divine doctrine. Preparation of heart is the unlearning the prejudices of evil converse. It is the smoothing of the waxen tablet before attempting to write on it.
It is more serious to lose hope than to sin. The traitor Judas was a defeatist, inexperienced in spiritual warfare; as a result he was reduced to despair by the enemy's onslaught, and he went and hanged himself. Peter, on the other hand, was a firm rock: although brought down by a terrible fall, yet because of his experience in spiritual warfare he was not broken by despair, but leaping up he shed bitter tears from a contrite and humiliated heart. And as soon as our enemy saw them, he recoiled as if his eyes had been burnt by searing flames, and he took flight...
Beguiling and deceptive is the life of the world, fruitless its labor, perilous its delight, poor its riches, delusive its honors, inconstant, insignificant; and woe to those who hope in its seeming goods: because of this many die without repentance. Blessed and most blessed are those who depart from the world and its desires.
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.
Trials are of two kinds. Either affliction will test our souls as gold is tried in a furnace, and make trial of us through patience, or the very prosperity of our lives will oftentimes, for many, be itself an occasion of trial and temptation. For it is equally difficult to keep the soul upright and undefeated in the midst of afflictions, as to keep oneself from insolence and pride in prosperity.
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).
What is self-justification? - Self-justification is when a man denies his sin, as we see in the case of Adam, Eve, Cain and others who have sinned but, wishing to justify themselves, denied their sin.
Fire makes iron impossible to touch, and likewise frequent prayer renders the intellect more forceful in its warfare with the enemy. That is why the demons strive with all their strength to make us slothful in attentiveness to prayer, for they know that prayer is the intellect's invincible weapon against them.
A single word made the thief pure and holy, despite all his previous crimes, and brought him into paradise (cf. Luke 23:42-43). A single ill-advised word prevented Moses from entering the promised land (cf. Num. 20:12). We should not suppose, then, that garrulity is only a minor disease. Lovers of slander and gossip shut themselves out of the kingdom of heaven.