"Always keep your mind collected in your heart," instructed the great teacher of prayer Saint Theofan the Recluse. The Jesus Prayer is part of a tradition of spiritual life that helps move the center of consciousness from the mind to the heart. Neither the mind nor the heart should be considered only in physical terms. The mind represents the analytic and organizational aspect of consciousness, the heart that part of the self most vulnerable to God's presence and most capable of experiencing God's love.
Use of the Jesus Prayer is one simple way of guarding the soul from preoccupation with the faults, real or imagined, of others. "A person is truly pure of heart when he considers all human beings as good and no created thing appears impure or defiled to him," wrote Saint Isaac of Syria, also known as Isaac of Nineveh.— Jim Forest, The Ladder of the Beatitudes