Two technical terms from theology: miaphysitism and hypostatic union. The first is the belief that Jesus combines divinity and humanity into one “nature” (“physis“); and the second is that there are two natures, divinity and humanity, united in one “substance” (“hypostasis“, also translated as “subsistence”, “essence”, or “person”).
One of those positions is orthodoxy and one is heresy, but which is which? Give up? Good decision.
In fact, the latter belief, hypostatic union, is the formal position of the Roman Catholic, Eastern Orthodox, and most Protestant churches. Only the churches of the Oriental Orthodox Communion disagree and stick to miaphysitism instead. (Mainly the Armenian, Coptic and Ethiopian Orthodox churches, accounting for most Christians in Armenia, Egypt and Ethiopia respectively.)
The split between the groups is one of the earliest in Christianity which still exists, dating to the Council of Chalcedon in 451 AD. Makes the Great Schism of 1054 look quite recent, never mind the Reformation.
Chalcedon was the fourth large ecumenical council held by the early Church, at the bidding of the Byzantine Emperors, to thrash out a common set of beliefs and practices. Much of the discussion, which could be heated, used Greek terminology such as “physis” and “hypostasis” which had been adopted from classical pagan philosophy, but often used vaguely or without proper definition. In the end, Chalcedon dodged the issue by declaring that hypostatic union was beyond human comprehension. You simply had to believe it.
When I read of the arguments from those times, I’m reminded of the scene in Monty Python and the Holy Grail where Sir Bedevere leads the peasants in a chain of medieval logic from burning witches to weighing ducks. I can imagine the minds working: “…but that would mean…” to another flight of fancy.
History doesn’t record whether anyone ever went: “Well, actually, this is all a load of bollocks.” because they wouldn’t then have bothered going along to a Council. It was probaly fairly rare anyway. But that is the characteristic of religious belief. Belief comes first, and then logic, of whatever kind the believer can muster, to flesh out the picture and resolve any issues.
If the believer is the kind of person who doesn’t think much or have many questions, faith is a simple thing; but for smart and inquisitive people, like the attendees of the Council of Chalcedon, the outcome is always convoluted and obscure. But they never cut the Gordian Knot by accepting that their core beliefs are illogical and contradictory. Beliefs are not susceptible to logic.
That’s why I rarely bother to argue with the religious, except occasionally out of mischief. It’s a battle you can’t win.