There are hundreds of books on prayer, and much of the advice they contain is likely to be the same. So what distinguishes these books? Call it a kind of wisdom, a sense that here's someone who knows something of God's heart. A good example can be found in this fine book by the Quaker writer and teacher Richard Foster. The author of the bestselling Celebration of Discipline explores various aspects of prayer, which he defines in one place as "the human response to the perpetual outpouring of love by which God lays siege to every soul." Beginning with the simplest forms of prayer--what he calls "ordinary people bringing ... ordinary concerns to a loving and compassionate Father"--he then explores the deeper places where prayer becomes not simply petition but a way of life. He writes of prayer of adoration and rest, sacramental prayer, meditation, and contemplation, and in the final section of the book moves outward into ministry, where prayer meets the needs of the world. In each chapter Foster defines, describes, and gives helpful examples. Above all he writes with grace--in both the artistic and spiritual senses.