Not of this World: A Treasury of Christian Mysticism, edited by Prof. James Cutsinger, challenges the notion that Christianity is a purely devotional path. It is widely supposed - by seekers whose contemplative journeys have taken them to the East - that the "love of God" is alone the primary obligation and the highest goal in a Christian's spiritual life, leaving no scope for contemplation as an integral part of this spiritual life. Not of this World invites the reader to explore a deeper and often overlooked dimension of Christian mysticism in which the accent is placed on the acquisition of gnosis (knowledge) and in which theosis (deification) is presented as the goal of the spiritual journey. Not of this World is a collection of short meditations on the contemplative life, drawn from a wide variety of Christian sources that range from the second to the twentieth centuries. Guided by writers whose backgrounds and experiences cross all sectarian divisions, the reader is invited to take part in a journey that follows the three classic stages of Purification, Illumination, and Union. Not of this World is unlike any previously published anthology of Christian mysticism by combining (1) primary sources drawn from nearly two thousand years of Catholic, Eastern Orthodox, and Protestant sources with (2) a focus on the acquisition of spiritual knowledge and "deification" as explicit goals of the Christian spiritual path. It is also unique as a book that can be as much at home on someone's bedside table, providing inspiration, as it can be within the classroom as a valuable teaching tool.