If a king wanted to take possession of his enemy's city, he would begin by cutting off the water and the food and so his enemies, dying of hunger, would submit to him. It is the same with the passions of the flesh; if a man goes about fasting and hungry the enemies of his soul grow weak.
For the complete fulfillment of its [the intellect's] purpose we should give it nothing but the prayer 'Lord Jesus'...Those who meditate unceasingly upon this glorious and holy name in the depths of their heart can sometimes see the light of their own intellect. For when the mind is closely concentrated upon this name, then we grow fully conscious that the name is burning up all filth which covers the surface of the soul; for it is written: 'our God is a consuming fire' (Deut. 4:24). Then the Lord awakens in the soul a great love for His glory...This is the pearl of great price which a man can acquire by selling all that he has, and so experience the inexpressible joy of making it his own.
Those who meditate unceasingly upon the holy and glorious name [of Jesus] in the depths of their heart can sometimes see the radiance of their own spirit-intelligence. For when the mind is profoundly concentrated on this invocation, we feel experientially how it starts burning off all the layers of dirt that normally suffocates the soul.
As wax cannot take the imprint of a seal unless it is warmed or softened thoroughly, so a man cannot receive the seal of God's holiness unless he is tested by labors and weaknesses. That is why the Lord says to St. Paul: 'My grace is sufficient for you: for My power comes to its fullness in your weakness'; and the Apostle himself proudly declares: 'Most gladly therefore will I rather glory in my weaknesses, so that the power of Christ may rest upon me' (2 Cor. 12:9).
Those pursuing the spiritual way should train themselves to hate all uncontrolled desires until this hatred becomes habitual. With regard to self-control in eating, we must never feel loathing for any kind of food, for to do so is abominable and utterly demonic. It is emphatically not because any kind of food is bad in itself that we refrain from it. But by not eating too much or too richly we can to some extent keep in check the excitable parts of our body. In addition we can give to the poor what remains over, for this is the mark of sincere love.
Monastic life is called the art of arts and the science of sciences; for it does not bring perishable blessings akin to the things of this world, which drive the mind from what is best and engulf it; but monk hood promises us wonderful and unspeakable treasures which the ' Eye that not seen, nor ear heard, neither have entered into the heart of man' (1 Cor. ii. 9). Hence, ' we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world' (Ephes. vi. 12). If therefore present existence is but darkness, let us flee from it, let us flee by returning our mind and our heart. Let us have nothing in common with the enemy of God, for 'whosoever will be a friend of the world is the enemy of God' ( James iv. 4). And who can help the enemy of God ? Therefore let us imitate our fathers and, like them, let us seek the treasure existing within our hearts and, having found it, let us hold fast to it in doing and guarding - for which task we were destined from the beginning.