Separation of church and state is relatively recent doctrine.
Notice in the States there is no official religion. An official religion by the state is a huge indicator of the unification of church and state.
Another indicator is if any religious priests seat any government positions.
Church and state worked hand in hand to manage the "souls bound to the land" for eons whether those souls were titled slaves, serfs, subjects, etc for harvesting of their energy.
The state is ultimately an alternative form of church/temple.
The state is ultimately a farm or plantation.