Khan, the head of the Sufi Order since 1956, opens his beautiful little book with a parable. Imagine, he says, you are a visitor from the far reaches of the universe and you have just landed on Earth. Whatever your reasons for coming to this planet, you assume the physical appearance of Earth's creatures and become adapted to its ways of life. Eventually, you suffer some kind of major upheaval. Feeling restless and uneasy, you begin to ask questions about the nature of reality, the source of creation and the beauty and mystery of the world. Suddenly, after years of searching, you remember your previous existence and you are awakened to your cosmic self and your oneness with the universe. Such a story, he notes, describes perfectly the essence of Sufism: "the story of every soul's descent into existence, its experiences of suffering brought about by separation from its original state of being, and the subsequent journey of return and reawakening to its Divine nature."