In the preface to the 1959 reissue of Brideshead Revisited, Waugh described the novel's theme as "the operation of divine grace on a group of diverse but closely connected characters." If you understand that Waugh equated divine grace with the Roman Catholic Church, you will grasp the book's central theme. Waugh believed his faith was the only way to counteract the modern decline of social traditions and the subsequent loss of individual self-assurance. His attempt to convey this in the novel led many critics to argue that Brideshead Revisited was merely a well-written religious tract.