This article uses ethnographic studies of Orthodox Christianities as a way to investigate the concept of ‘orthodoxy’ as it applies to religious worlds. Orthodoxy, we argue, is to be found neither in opposition to popular religion nor solely in institu- tional churches, but in a set of encompassing relations among clergy and lay people that amounts to a religious world and a shared tradition. These relations are characterized by correctness and deferral—formal modes of relating to authority that are open-ended and non-definitive and so create room for certain kinds of pluralism, heterodoxy, and dis- sent within an overarching structure of faith and obedience. Attention to the aesthetics of orthodox practice shows how these relations are conditioned in multi-sensory, often non-linguistic ways. Consideration of the national and territorial aspects of Orthodoxy shows how these religious worlds of faith and deferral are also political worlds.