how to explain church miracles?

[Esquilax]

Also, even if we didn't have an explanation, to leap directly to "it's a miracle," is just an argument from ignorance. The best you could say is that this is a thing with a currently unknown explanation. Even leaving aside every other contention brought up in this thread, it's the churchies claiming that this stuff is miraculous that would need to demonstrate that, and the fact that they're more than happy assuming these things are miracles is fairly telling.