You seem to have this same problem i see inmany christian to think the bible and catholic church is the start of studying god spurituality and religion, but its much older than it.
Actually plato was already denouncing all the problem from materialism, and body that is distraction from spiritual truth, and all the thing you speaks about relating dogma , dialog, trinity, and all that jazz.
It was way before the new testament and the new testament is mostly a compilation of older gnostic wisedom.
Even the old testament is very inspired from more ancient myth like summerian or babylonian or egyptian.
Plato already speaks of the body as tomb of the soul, of the prisoner cave, and all those stuff centuries before christianism.
Religion is mostly binding, its mostly catholics who have this mentality of self sacrifice for tje supposed superior good of the church, which in my book spells stalinism.
God made man in its image, and if god can be materialized in something in this plane its in human soul.
Having this sort of binding to hierarchical totalitarian organisation like catholic church is far from being benefitial on any level.
I guess to a degree spiritual practice in the gnostic sense tends to prone detachment from the body and materialism, to focus more on morality, idealism, and spiritual thing, in the sense knowledge of the spirit, but spirit and body are always connected to each others, and i would say its hard to master the mind and spirit without first mastering the body and physical plane.
But this idea is very old, people like pythagora, plato, parmenides, euclid, philo of alexendria etc were always studying this connection between abstract thinking, rationalism, geometry, logic, and the nature of reality, rather than focusing on sensorial perception of the material world coming from the body.
It can be traced way back to toth/hermes with the unseen that govern manifestation of reality, that is the pontential of things to become what they will become. Like distinction between what already happened before as the past/memory, the seen world, and the energy as the unseen that guide manifestation of the future.
Materialism is focusing on the seen, and originally, both science and spirituality are concerned with the unseen law at play in the universe, as in mathematics, metaphysics, equations, energy etc.
It doesnt matter that much if the form taken by the teaching is a hierachical church preaching a dogma, what matter is how it helps to see the unseen, to discover the truth as in god will.
As no one has found the ultimate dogma of what is god will, to unveil the whole law of karma ans such, and all dogmatic teaching with totalitarian pretense come at the price of sacrifying some part of truth.
RE: Divine Revalation or Man's imagination, How do you know?