““A religion that dies in one area, in the sense of having no known active followers, may have many covert or clandestine believers, and—rather like the collapse of churches—crypto-Christianity is a thoroughly understudied phenomenon. In theory, true hidden believers should be immune to study, as they never break cover, and the people who can be studied are only the less discreet. But we often do hear of crypto-Christians, and the stories are startling, all the more so for Westerners accustomed to thinking of Christianity as the established faith of states.””
