Lewis Sperry Chafer was a prominent American theologian and Christian writer. Chafer was the first president of the Dallas Theological Seminary and he contributed significantly to Christian Dispensationalism in the early 20th century. Chafer is best remembered today for his books, including the Christian classic He That is Spiritual. In the book He That is Spiritual, published in 1918, Chafer analyzes the biblical teaching of how to live a spiritual life.