I do not believe it exists. If it is never, then it must not exist.
proofs I would accept:
(for Christianity)
Biblically accurate angels descend onto earth, to everyone, and submit themselves to scientific testing, which conclude they are made of something non-physical.
Divinity is proven to be a measurable and testable attribute of reality.
Reality warping magic, demonstrated to not be any sort of trick or technology, and limited to those devout to said religion.
God shows his ass to everyone, the only part of him that - according to the bible - won't make a human insane.
the basis of these proofs can be distilled down to some basic requirements: - It must happen in 'reality' not 'in my head'. - It must be testable, and repeatable. - It must have no 'natural/scientific' explanation. - It must be viewable by everyone.
That's not 'all' of the requirements, but regardless of which religion we are talking about: those are the common primitives.
Nothing I've encountered have met these standards. But if those standards of mine are met...
> "But if those standards of mine are met..."
> "Biblically accurate angels descend onto earth, to everyone, and submit themselves to scientific testing, which conclude they are made of something non-physical."
You would easily agree that something which can be seen, touched, measured, interact with the sky, your eyes, and measuring equipment is "non-physical"? You wouldn't suspect the angels are instead aliens?
> "Divinity is proven to be a measurable and testable attribute of reality."
At this point, if it happened then it's unlikely to be in the macro-scale world that we could all test with an easily available and usable thermometer or film camera or alkalinity measuring strip, because we would probably have noticed that by now. Imagine instead it's a paper from CERN and the Large Hadron Collider where in some extreme situation there's a deviation of 0.0000000<whatever>% from an expected value and experts in Quantum Theology claim that's a testable, repeatable, measure of Divinity. Are you tempted to believe this could happen, or are you already full of reasons to dismiss it?
> "Reality warping magic, demonstrated to not be any sort of trick or technology, and limited to those devout to said religion."
Mass warps spacetime and curves light rays. That's neither trick nor technology. It's arguably "limited to those devout to physics" in the sense that Flat Earthers might not accept it and primitive/uneducated tribes have no grounds for understanding what it means at all and no ability to build machines to test it. Similar with Young's double slit experiment, Lorentz contraction, entanglement, and others (reality warping, or brain warping?).
> "God shows his ass to everyone, the only part of him that - according to the bible - won't make a human insane."
What would it take for you to agree that that's whose ass it was?