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.
In the eyes of God, it is always preeminently right that a man should spend himself in devising new means for spreading consolation to his subordinates, who are his charges.
Do not by any means allow yourself to open both ears to the slanderers and to draw your conclusions and decisions on the basis of what they alone have to say, and thereby judging the case in absentia without the presence of the person slandered to defend himself. Oftentimes many unjust and irrational decisions have followed from such slanderous accusations.
Do not lend your ear to the tongue of the slanderer, nor your tongue to the ear of him who likes malicious talk, speaking or listening with enjoyment to words against one's neighbor. Cut yourself off from them, lest you fall away from love of God and find yourself exiled from eternal life.
There is a difference, Dearly Beloved Brethren, between the delights of the body and those of the soul, that the delights of the body, when we do not possess them, awaken in us a great desire for them; but when we possess them and enjoy them to the full they straightway awaken in us a feeling of aversion. But spiritual delights work in the opposite way. While we do not possess them we regard them with dislike and aversion; but once we partake of them we begin to desire them, and the more do we hunger for them. In one case the appetite pleases, the reality brings displeasure; in the other it is the appetite [that] displeases, the reality delights us more and more. In the one case appetite leads to fullness, and fullness to disgust; in the other appetite begets fullness, and fullness in turn begets appetite. For spiritual delights, when they fill the soul, increase in us a desire of them; and the more we savor them, the more do we come to know what we should eagerly love.
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.
If you have spoken evil of your brother, and you are stricken with remorse, go and kneel down before him and say: 'I have spoken badly of you; let this be my surety that I will not spread this slander any further.' For detraction is death to the soul.
An elder prescribes the following rule of conduct for the monastic table: 'When you sit to eat, brother, do not be overcome by the demon of gluttony, which compels you to eat in a disorderly way and in haste and to desire to taste many kinds of food together. Learn to eat modestly and in an orderly way and maintain a measure of restraint.'
You write that after Communion you felt well. Glory be to God, Who comforts our unworthiness. And as regards the fact that this soon passed, here also is seen His fatherly providence for us. For continual consolation enfeebles the soul and makes it slothful, or leads to even greater harm. That is why the Lord takes it away quickly and again makes us feel our weakness, our helplessness, and our sinfulness. We must humble ourselves more, reproach ourselves, offer repentance for our sins, and not desire consolations, but patiently endure what God allows. Dryness and cooling of fervor are also permitted on account of vainglory.
Let us be satisfied simply with what sustains our present life, not with what pampers it. Let us pray to God for this, as we have been taught, so that we may keep our souls unenslaved and absolutely free from domination by any of the visible things loved for the sake of the body. Let us show that we eat for the sake of living, and not be guilty of living for the sake of eating. The first is a sign of intelligence, the second proof of its absence.