The fault lines
The place where separation and division are most obvious, from one church denomination to another, is in church government: the question of whose hierarchy and ecclesiology and methods of organization are going to be in control. There is nothing peculiar about that, I suppose. But it is an obstacle to unity, for it raises the question of who shall be in charge in, and after, any unification effort. People can be a bit touchy about that. Defending their doctrines and stances and historical witness becomes wrapped up with, simultaneously, protecting their own power and prestige. No one seems willing to become the lesser so that unity can be gained, as the greater objective. That is human nature, but we will need something beyond merely human nature to solve our schisms. Thus I propose a little challenge, a thought experiment. Can you conceive of any circumstances in which you would support surrendering your accustomed form of church government, and/or putting new people in charge, if