As a general, formal matter, this point holds even though different Christian groups disagree about what the constraints of orthodoxy actually are. So Roman Catholic Christians and Protestant Christians will accept different constraints about, say, the nature of the Eucharist, and rival Protestant Christian groups will differ with each other in a similar way. But as a formal matter, Christian thinkers who think philosophically about Christian doctrines typically do so inside the intellectual framework provided by what they regard as authoritative Christian orthodoxy. Obviously, it is not the case that everyone who wants to think philosophically about Christianity must accept the constraints of Christian orthodoxy, even in this more relativistic sense of “orthodoxy”. Some modern and contemporary thinkers still identify as Christians even though they reject the very idea of normative orthodoxy, for example. And, of course, non-Christian thinkers, including non-theists, will reject any notion of Christian orthodoxy in its entirety. Yet they can still think philosophically about Christian doctrines.