“…they [Church Fathers] selected just a few words in a single, simple prayer, “Lord Jesus Christ, Son of God, have mercy on me” , so that the mind would not require a great effort in order to hold on to a long, protracted prayer. Secondly, they turned the mind within, to the center of our reason, where it resides motionless with the meaning of the divine invocation…in order to experience as soon as possible the divine consolation.”
(Elder Joseph of Vatopedi+, ‘Prayer of the Heart’)
 

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