Intelligent Christians not only lead lives of prayer, but also require an understanding of prayer. Too often we are told how to pray, but not why we pray. Too often we are asked to recite our creeds, but not to explore how they express our faith. This first American edition of Thornton's classic work provides inquisitive Christians with a map for an informed life of prayer. Drawing on the work of Macquarrie and Buber, Thornton illuminates the nature of the Trinity as the ground of our existence, and the eucharist as our ultimate form of prayer.