How do the doctrine of the Assumption and the doctrine of the Dormition differ? And, if they differ, how can two Churches united in faith belief differing doctrines?
There really is no difference between the “Dormition” and the “Assumption.” If there is a difference, it is entirely in emphasis. The Latin feast of the Assumption tends to emphasize Mary’s bodily assumption into heaven. The Eastern feast of the Dormition, as depicted in iconography, emphasizes Mary falling asleep, and her body later being taken to heaven. But from a doctrinal standpoint, there is no conflict.