When a man gives God his secret things, that is, his mind and thoughts, not occupying himself elsewhere, nor wandering away, but putting constraint upon himself, then the Lord deems him worthy of mysteries, in greater sanctity and purity, and gives him heavenly food and spiritual drink
What good is it to keep meat out of your mouth if you bite your brother with wickedness? What good does it serve you to observe a strict frugality at home if you unjustly steal from the poor? What kind of piety teaches you to drink water while you hatch plots and drink the blood of a man you have shamefully cheated? Judas, after all, fasted along with the eleven, but failed to master his greed; his salvation gained nothing by fasting. And the devil does not eat, for he is an incorporeal spirit, but he fell from on high through wickedness. Likewise, none of the demons can be accused of gorging themselves, of excessive drinking or getting drunk, for their nature makes feeding unnecessary; nevertheless, night and day, they roam through the air, agents and servants of evil, eager for our loss. They ooze with bitterness and jealousy—things it is well to avoid—at the idea that humans may enter into an intimacy with God, since they have fallen from the supremely worthy dwelling.
A greedy appetite for food is terminated by satiety and the pleasure of drinking ends when our thirst is quenched. And so it is with the other things... But the possession of virtue, once it is solidly achieved, cannot be measured by time nor limited by satiety. Rather, to those who are its disciples it always appears as something ever new and fresh.
Four monks of Scetis, clothed in skins, came one day to see the great Pambo. Each one revealed the virtue of his neighbor. The first fasted a great deal; the second was poor; the third had acquired great charity; and they said of the fourth that he had lived for twenty-two years in obedience to an old man. Abba Pambo said to them, 'I tell you, the virtue of this last one is the greatest. Each of the others has obtained the virtue he wished to acquire; but the last one, restraining his own will, does the will of another. Now it is of such men that the martyrs are made, if they persevere to the end.'
Unless humility and love, simplicity and goodness regulate our prayer, this prayer - or, rather, this pretence of prayer - cannot profit us at all. And this applies not only to prayer, but to every labor and hardship undertaken for the sake of virtue.
St. John Climacus was asked if there are reliable signs by which it's possible to know whether a soul is drawing near to God or moving away from Him. After all, regarding ordinary things there are clear signs as to whether they're good or not. When, for instance, cabbage, meat or fish begins to rot, it's easy to notice it, since the rotting object begins to give off a foul odor, the color and taste change, and its external appearance witnesses to its deterioration. Well, and what about the soul? After all, it's bodiless and can't give off a bad smell or change its appearance. To this question the Holy Father replies, 'A sure sign of the deadening of the soul is the avoidance of church services.'
Just as gold is found, washed out of a great amount of sand and it amounts to very small grains like millet, so also out of many human beings few will be approved. For those who seek the kingdom are clearly manifested, while those who merely wear its word as a beautiful ornament are the ones most conspicuous. For the same reason those are manifested who are seasoned with the heavenly salt and who speak out of the Spirit's treasures. The vessels appear in whom God is pleased and to whom He gives His grace. There are also others, who, with much patience, receive the sanctifying power in many different ways, as God wishes.
For as merchants on a voyage, though they find a wind to suit them and the sea calm, but have not yet reached the haven, are always subject to fear, lest suddenly a contrary wind should stir and the sea rise into billows, and the ship be in peril, so Christians, even if they have in themselves a favorable wind of the Holy Spirit blowing, are nevertheless yet subject to fear, lest the wind of the adverse power should rise and blow on them, and stir disturbance and billows for their souls. There is need therefore of great diligence, that we may arrive at the haven of rest, at the perfect world, at the eternal life and pleasure, at the city of the saints, at the heavenly Jerusalem, at the church of the firstborn (Heb. xii. 23.). Unless a man gets through these measures, he is under much fear, lest in the meantime the evil power should effect some fall.