As a man cannot remain unscathed who spares his enemy on the field of battle, so a man engaged in spiritual warfare cannot save his soul if he spares his body.
Use your body, I beseech you, with moderation. Remember, with this body you will be raised from death when you come to be judged. Perhaps you have some doubt whether this could happen. If so, reflect in detail on what has already happened with your own self. Tell me, where were you a hundred years ago? Cannot the Creator who gave existence to a person that did not exist bring to life again to a person that did exist but is now dead? Every year He makes the corn spring to life that had withered and dies after it was sown. Do you suppose that He who raised Himself from the dead for our sake will have difficulty in raising us to new life? Or look at the trees. For a number of months they remain without fruit, even without leaves. But once the winter is past, they become green all over, new, as if risen from the dead. With better reason, and with greater ease shall we be called to new life. Do not listen to those who deny the resurrection of the body. Isaiah testifies: ‘The dead shall live again: the bodies of those who have died shall live.’ (Isa. 26:19) And according to the word of Daniel, ‘Many of those who sleep beneath the earth shall awaken, some to life eternal, the rest to eternal ruin.’ (Dan. 12:2)
Charity, temperance, contemplation, and prayer please God; gluttony, licentiousness, and what multiplies them, please the flesh. Therefore they who are in the flesh cannot please God. And they that are Christ’s have crucified their flesh with the passions and concupiscences.
The moral character and moral value of man's personality depends most of all on the direction and strength of the will. Of course, everyone understands that for a Christian it is necessary to have first, a strong and decisive will, and second, a will which is firmly directed toward the good of his neighbor, toward the side of good and not evil. How is one to develop a strong will? The answer is simple: above all through the exercise of the will. To do this, as with bodily exercise, it is necessary to begin slowly, little by little. However, having begun to exercise one's will in anything ( e.g., in a constant struggle with one's sinful habits or whims) this work on oneself must never cease. Moreover, a Christian who wishes to strengthen his will, his character, must from the very beginning avoid all dissipation, disorder and inconsistency of behavior. Otherwise, he will be a person without character, unreliable, a reed shaking in the wind, as we read in Holy Scripture.
And pray ye without ceasing in behalf of other men. For there is in them hope of repentance that they may attain to God. See, then, that they be instructed by your works, if in no other way. Be ye meek in response to their wrath, humble in opposition to their boasting: to their blasphemies return your prayers; in contrast to their error, be ye steadfast in the faith; and for their cruelty, manifest your gentleness. While we take care not to imitate their conduct, let us be found their brethren in all true kindness; and let us seek to be followers of the Lord (who ever more unjustly treated, more destitute, more condemned? ), that so no plant of the devil may be found in you, but ye may remainin all holiness and sobriety in Jesus Christ, both with respect to the flesh and spirit.
No one can be saved without the renunciation of his will, even though he might struggle fervently, for our will and our manner are like a bronze wall between us and God.
When the flesh flourishes, the soul fades; when the flesh has full liberty, the soul is straitened; when the flesh is satiated, the soul hungers; when the flesh is adorned, the soul is deformed; when the flesh overflows with laughter, the soul is surrounded by misfortune; when the flesh is in the light, the soul is in darkness...
Unceasing prayer means to have the mind always turned to God with great love, holding alive our hope in Him, having confidence in Him whatever we are doing and whatever happens to us. That is the attitude that the Apostle had when he wrote: ‘Who shall separate us from the love of Christ? Shall tribulation, or distress, or persecution, or famine, or nakedness, or peril? Neither death nor life nor any other creature shall be able to separate us from the love of God in Christ Jesus.’ [cf. Rom. 8:35-38]
Having guarded ourselves against distractions and worries, let us turn our attention to our body on which mental vigilance is completely dependent. Human bodies differ widely from one another in strength and health. Some by their strength are like copper and iron; others are frail like grass. For this reason everyone should rule his body with great prudence, after exploring his physical powers. For a strong and healthy body, special fasts and vigils are suitable; they make it lighter, and give the mind a special wakefulness. A weak body should be strengthened by food and sleep according to one's physical needs, but on no account to satiety. Satiety is extremely harmful even for a weak body; it weakens it, and makes it susceptible to disease. Wise temperance of the stomach is a door to all the virtues. Restrain the stomach, and you will enter Paradise. But if you please and pamper your stomach, you will hurl yourself over the precipice of bodily impurity, into the fire of wrath and fury, you will coarsen and darken your mind, and in this way you will ruin your powers of attention and self-control, your sobriety and vigilance…