Just as it is impossible to cross the sea without a boat, so it is impossible to repulse the provocation of an evil thought without invoking Jesus Christ.
Almsgiving heals the soul's incensive power; fasting withers sensual desire; prayer purifies the intellect and prepares it for contemplation of created beings. For the Lord has given us commandments which correspond to the powers of the soul.
All Christians, clergy, laity and monks, when rising from sleep must first think of and remember Christ. They must offer this remembrance to Christ as a sacrifice and first-fruits of every thought (Hebrews 13:15). For we must remember, before every thought, Christ Who saved us and has loved us so greatly, for we are, and are called, 'Christians'. We put him on by divine Baptism (Gal. 3:27), and we were sealed with His Chrism. We have partaken, and do partake, of His holy Body and Blood. We are His members (I Cor. 12:27) and His temple (II Cor. 6:16). Him do we put on, and He dwells in us. For this reason we are obliged to love Him and remember Him always. Wherefore, let everyone devote time, according to his ability, and have a certain amount of this prayer as an obligation. And this suffices concerning this matter, for this is a sufficient amount of instruction for those who seek concerning it.
Continually say the Prayer [of Jesus] intensely, with zeal, with longing; only thus does one become strong in soul. Avoid idle words by means of all sacrifice, for they weaken the soul and it does not have the strength to struggle.
My brother, the passions are afflictions; and so the Lord does not excommunicate us because of them, but He says: 'Call upon me in the time of affliction; and I will deliver thee, and thou shalt glorify me'. Therefore, when beset by any kind of passion, there is nothing more useful than to call upon the Name of God. All we can do, weak as we are, is to flee for refuge to the Name of Jesus. For the passions, being demons, retreat if this Name is invoked.
At this point the zealous man looks inward, and what do you think he finds there? Ceaseless wandering of thoughts, constant onslaughts from the passions, hardness and coldness of heart, obstinacy and disobedience, desire to do everything according to his own will. In a word, he finds everything within himself in a very bad state. And seeing this, his zeal is inflamed, and he now directs strenuous efforts to the development of his inner life, to controlling his thoughts and the dispositions of his heart. From directions on inner spiritual life he discovers the necessity of paying attention to oneself, of watching over the movements of the heart. In order not to admit to anything bad, it is necessary to preserve the remembrance of God. And so he sets to work to achieve this remembrance. But his thoughts can no more be arrested than the wind; his bad feelings and worthless impulses can no more be evaded than the stench of a corpse; his mind, like a wet and frozen bird, cannot rise to the remembrance of God. What is to be done? Be patient, they say, and go on working. Patience and labor are exercised, but all within remains the same. At last someone of experience is found who explains that all is inwardly in disorder because the forces within are divided: mind and heart each go their own way. Mind and heart must be united; then wandering of thoughts will cease, and you will gain a rudder to steer the ship of your soul, a lever by which to set in movement all your inner world. But how can one unite mind and heart? Acquire the habit of praying these words with the mind in the heart, 'Lord Jesus Christ, Son of God, have mercy upon me'. And this prayer, when you learn to perform it properly, or rather when it becomes grafted to the heart, will lead you to the end which you desire. It will unite your mind with your heart, it will cut off your wandering thoughts, and give you the power to govern the movements of your soul.
It is as necessary for a man to say the Jesus Prayer as it is for a ship in danger to send out steadily the S.O.S. signal: Lord Jesus Christ have mercy on me.
Do not hesitate to go late at night to those places where you usually feel afraid. But if you yield only a little to such weakness, then this childish and ridiculous infirmity will grow old with you. As you go on your way, arm yourself with prayer. When you reach the place, stretch out your hands. Flog your enemies with the name of Jesus, for there is no stronger weapon in heaven or earth. When you get rid of the disease of fear, praise Him who has delivered you. If you continue to be thankful, He will protect you for ever.
Please put this commandment into practice. Cultivate love towards the Person of Christ to such an extent that, when you pronounce His name, tears fall from your eyes. Your heart must really burn. Then He will become your teacher. He will be your Guide, your Brother, your Father, and your Elder.
Join to every breath a sober invocation of the name of Jesus and the thought of death with humility. Both these practices bring great profit to the soul.
The power given by the Lord to His seventy disciples is given to all Christians (Mk. 16:17). Use it, Christian! With the name of Jesus cut off their heads, that is the first appearances of sin in our thoughts, fancies and feelings. Destroy within you the devil's rule over you; destroy all his influence over you; acquire spiritual freedom. The foundation for your struggle is the grace of holy baptism; your weapon is prayer in the name of Jesus.
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.
Moreover, bear in mind the method of prayer – how it is possible to pray without ceasing, namely by praying in the mind. And this we can always do if we so wish. For when we sit down to work with our hands, when we walk, when we eat, when we drink we can always pray mentally and practice this mental prayer – the true prayer pleasing to God.