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.
Just as we must beware of overeating, so too we must beware of excessive temperance or abstinence. Excessive temperance weakens the body, destroys wakefulness, coolness and freshness which are indispensable for vigilance, and which fade and weaken when the physical powers succumb and fail. If you force a weak body to labor beyond its powers, you subject your soul to double darkness, and lead it into confusion (and not relief)...
Prayer offered up at night possesses a great power, more so than the prayer of the day-time. Therefore all the righteous prayed during the night, while combating the heaviness of the body and the sweetness of sleep and repelling bodily nature.
It is just as shameful for lovers of the flesh and the belly to search out spiritual things as it is for a harlot to discourse on chastity. A body suffering grave illness shuns fatty foods and abhors them; and likewise, a mind occupied with worldly affairs cannot approach the inquiry into things of God. A fire cannot be ignited with wet wood, nor can the divine fervor be kindled in a heart that loves ease.
The key to Divine gifts is given to the heart by love of neighbor, and, in proportion to the heart's freedom from the bonds of the flesh, the door of knowledge begins to open before it.
What salt is for any food, humility is for every virtue. To acquire it, a man must always think of himself with contrition, self-belittlement and painful salf-judgment. But if we acquire it, it will make us sons of God.
It is impossible for the soul to be liberated from turbulent thoughts without the virtue of non-possessiveness. And without peace of the bodily senses it is impossible for the soul to have a peaceful intellect. And if it does not come into temptations it will not acquire wisdom of the Holy Spirit. And without laborious and persistence in reading, it will not come to the discernment of thoughts. And without the stillness of thoughts, the intellect cannot move to seek the hidden mysteries of God.
But if you give a strong body rest and ease and idleness, all the passions dwelling in the soul are intensified. Then, even if the soul has a great desire for good, even the very thought of the good that is desired will be taken from you.
A life of spiritual endeavor is the mother of sanctity; from it is born the first experience of perception of the mysteries of Christ--which is called the first stage of spiritual knowledge.
The angel who is always near us is by nothing so distressed and made indignant as when, without being constrained by some necessity, we deprive ourselves of the ministration of the Holy Mysteries and of reception of Holy Communion, which grants remission of sins. For at that hour the priest offers up the sacrifice of the Body of Him Who gives us life, and the Holy Spirit descends and consecrates the Body and Blood and grants remission to creation. The Cherubim, the Seraphim, and the angels stand with great awe, fear, and joy. They rejoice over the Holy Mysteries while experiencing inexpressible astonishment. The angel who is always by us is consoled, because he also partakes in that dread spectacle and is not deprived of that perfect intercourse.
