Carl Jung once wrote, "No matter what the world thinks about religious experience, the one who has it possesses a great treasure." Although fewer people than ever go to church, research indicates that perhaps as many as 66% of the population in secularized English-speaking countries are having significant religious experiences. This book explores the causes, nature, and effects of such experiences whether theistic or non-theistic, while indicating how those which are theistic can animate Christian spirituality, theology, piety, and churchgoing, while improving the psychosomatic health of those who enjoy them. This well-informed, wide-ranging study is a fascinating apologia which advocates the importance, beauty, and life-transforming power of a vital but often neglected dimension of human existence. It also sounds a cautionary note by pointing out that the orthodoxy of religious experience must be measured against the parameters of traditional Christian teaching in the belief that while dogmatic faith without religious experience is lifeless, religious experience without dogma is blind.