Because the nous can get tired by the reciting of all the words of the Jesus Prayer, it is necessary to make it shorter: 'Lord Jesus Christ, have mercy on me.' Or, 'Lord have mercy on me.' Or, 'Lord Jesus.' As the Christian progresses in the work of the Jesus Prayer, he can decrease the words. He can even sometimes insist on the word 'Jesus,' which he says repeatedly (Jesus, Jesus, Jesus, my Jesus)--a wave of calmness and joy rises in him. He should remain in this sweetness which appears and not stop the prayer, even if his usual rule of prayer is finished. He should seize and keep this warmth of his heart and take advantage of this gift of God! For it is a great gift which God sends from on high. The warmth of the heart helps the nous effectively to be fixed on the words of the Jesus Prayer ... If one wants to spend all day in prayer, he should follow the recommendation of the Holy Fathers. He should pray for an hour, read for an hour and then again spend an hour in prayer. When he is engaged in manual work too, he should try to say the Jesus Prayer.
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.
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.
Our good Redeemer, by speedily granting what is asked, draws to His love those who are grateful. But He keeps ungrateful souls praying a long time before Him, hungering and thirsting for what they want, since a badly trained dog rushes off as soon as it is given bread and leaves the giver behind.
And as with regard to raiment and gold, when we expose them in a market-place, we attract many ill-meaning persons; but if we put them by at home and hide them, we shall deposit them all in security: even so with respect to our good deeds; if we are continually keeping them in memory, we provoke the Lord, we arm the enemy, we invite him to steal them away; but if no one know of them, besides Him who alone ought to know, they will lie in safety. Be not therefore for ever parading them, lest some one should take them away. As was the case with the Pharisee, for bearing them about upon his lips; whence also the devil caught them away. And yet it was with thanksgiving he made mention of them, and referred the whole to God. But not even did this suffice Him. For it is not thanksgiving to revile others, to be vainglorious before many, to exalt one's self against them that have offended. Rather, if thou art giving thanks to God, be content with Him only, and publish it not unto men, neither condemn thy neighbor; for this is not thanksgiving.
Prayer is the mind's dialogue with God, in which words of petition are uttered with the intellect riveted wholly on God. For when the mind unceasingly repeats the name of the Lord and the intellect gives its full attention to the invocation of the divine name, the light of the knowledge of God overshadows the entire soul like a luminous cloud.
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.
When God is thanked, He gives us still further blessings, while we, by receiving His gifts, love Him all the more and through this love attain that divine wisdom whose beginning is the fear of God (cf. Prov. 1:7).
'Lord Jesus Christ, Son of God, have mercy on me, a sinner.' Let your attention and instruction be centered on this. Walking, eating, standing in church before the beginning of the service, continue with the prayer; on entering and departing keep this prayer on your lips and within your heart. In such a manner, with the invocation of the Name of God you will find peace, you will attain to purity of spirit and body; and the Holy Spirit, the Origin of all good, will make for Himself a dwelling within you and will guide you in all piety and purity.
One time St. Nicodemos, on a feast day, was walking toward the Great Lavra (on Mt Athos). On his way he came across a kellion where he spent the night. At midnight he saw an elder and his accompanying monks entering the church. He secretly went in also, and there he saw the elder and his subordinate monks uttering the Jesus Prayer ('Lord Jesus Christ, Son of God, have mercy on me'), sometimes in a kneeling position, sometimes standing up. And at the time of the Holy Communion, he saw all their faces shining only a little less dimly than the sun.
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.
Blessed are those who acquire the habit of this heavenly practice (unceasing prayer in the name of Jesus), for by it they overcome every temptation of the evil demons, as David overcame the proud Goliath. It extinguishes the unruly lusts of the flesh, as the three men extinguished the flames of the furnace. This practice of inner prayer tames passions as Daniel tamed the wild beasts. By it the dew of the Holy Spirit is brought down upon the heart, as Elijah brought down rain on Mount Carmel.