Book excerpt: The Jesus Prayer has been with us since the earliest years of Christianity. With its many variations, from “Lord Jesus Christ, son of God, have mercy on me, a sinner" to the single word “Jesus” it has been a fount of prayer and a way of being attentive to God for the monks, nuns, clergy and lay people of the Eastern Church for centuries. Today, the Jesus Prayer is practiced all over the world in every Christian tradition. Simple in form, but powerful in its potential to develop and transform the heart, it becomes a way of life for those who practice it. This short, simple guide is ideal for all who are new to this ancient spiritual practice and all who are learning to make it part of their daily practice of prayer.