Over the years, several people have asked about the Jesus Prayer and how to use it. I would like to share an answer I received from Metropolitan Anthony Bloom, some thirty-six years ago.
To use a phrase of Theophan the Recluse: the Jesus Prayer is not a talisman or an amulet, and although the powers of darkness cannot hear the holy name of Jesus without fear, it has no magic power over us. Anyone can use it if he does so with simplicity of heart (not as though he was engaging in a mysterious mystical exercise) and if the words are really meant; i.e., express a need and sincere attitude of mind.
To use it, you must be deeply, intensely, sincerely, aware that you are in need of God and that only in Him is salvation for you. To say that you are a sinner means just that; a sinner is one who is afraid of depth, who shrinks away from his own depth, who feels safer on the superficial levels of his being and his life, to whom the storms life experienced on its surface are more familiar, and seems to be safer than all the serenity and peace of the deep. As a result, the sinner cannot reach God who lives as the core of his being, cannot relate otherwise that superficially (in fear, greed, hatred, aggression, etc.) to his neighbor. If you are in this condition and are aware, painfully aware of it, you can honestly call yourself a sinner before God, and speak the other words of the Prayer.
The beginning of it is a complete profession of faith, which implies more than “believing,” but also the corresponding “doing.” Faith without works is dead. If you wish to call Jesus “Lord,” you must think out the implications of his “Lordship” in your personal life and set out ruthlessly without self-pity, to bring about in all your actions, thoughts, feelings, acts of will and desires. “Have mercy” covers a vast ground—“let your anger cease, grant me gratuitously your forgiveness, give me time and scope to change my life.” Read the Prayer of Manasseh; it means “heal me” (I am sick in soul and body, with the sickness of corruption), pour upon me your grace, that I may fulfill my vocation, which is your will. What is impossible to men is possible for God-in brief, become partakers of the Divine Will.
If you are aware of your desperate need, then cry to God in the brief invocation which the Jesus Prayer provides, but do not imagine that you are doing something meritorious or mystical or great—a drowning man has little cause to be proud of howls for help, salvation. Pay no attention to any feelings or physical phenomena. Take as a criterion for having prayed well a new and more ruthless readiness to do God’s will—humbly, unassumingly, and inconspicuously in His commandments. Let no one ever notice you are taking life seriously. One never pays too high a price in order to remain unnoticed.