In Optina, during the time of Elder Macarius, there was a monk who often came to the Elder for advice, obviously with a sincere desire for correction. The Elder told him that the closest path to perfection is the unceasing practice of the Jesus Prayer.
“Why that prayer in particular, Batiushka?” objected the monk. “After all, there’s nothing said about it in the Gospels.”
“And do you read the Gospels?”
“Of course – a chapter a day.”
“Well, if you read them, then you must remember the words of the Savior, ‘In My Name shall they cast out devils’.”
The monk began to practice the Jesus Prayer. Some time later he again came to Fr. Macarius with sorrow.
“Well, what is it, brother?” asked the Elder.
“I’m doing the Jesus Prayer, Father, but what kind of benefit can there be from it if I pronounce it only with my lips, not understanding what I’m saying? My mind keeps running off.”
“You may not understand,” said the Elder, “but then again, the demons understand and tremble. Be at peace, brother, and continue the Prayer according to your strength.”
A little time went by after this conversation and the monk came to see the Elder. With joy he informed him that the Jesus Prayer had revealed the mysteries of God to him.
The Elder said to him, “Don’t pay attention to it and don’t attach any importance to it.”
Soon the monk again informed Fr. Macarius about those spiritual gifts which the Jesus Prayer grants one, and again the Elder forbade him to attach any meaning to it. But to others Fr. Macarius reported what a great mercy of God the brother had been make worthy of in such a short time. They objected, “But so-and-so has been doing the Jesus Prayer for many years and has no revelations. What’s the cause of this?”
“A lack of humility,” said the Elder.
spotted in the Bulletin of Holy Theophany Orthodox Church
http://thehandmaid.wordpress.com/2011/10/03/unceasing-practice-of-the-jesus-prayer/