The mystics of the twelfth and thirteenth centuries were, writes Karen Armstrong, like "the astronauts of our own day. They broke into a new religion, blazed a new trail to God and to the depths of the self, a trail far from the beaten pilgrimage paths of Chaucer and Langland." Mysticism is a spiritual mystery shared in some form by all faiths; it has a supernatural quality that extends beyond the given boundaries of religious creed and may be experienced...