Sequel to The Inquiry, What Is Revelation? In A Series of Letters to a Friend (1860) is a book written by Frederick Denison Maurice. It is a continuation of the author's earlier work, The Inquiry, which explores the nature of revelation and its role in religious belief. In this sequel, Maurice continues his discussion of these topics, but in the form of a series of letters to a friend. The letters cover a wide range of subjects related to religion,...