Many good questions, none of which can be satisfactorily answered.
One may rise above conceit, dispense with ego, escape the human delusion. But this is vanishingly rare, and anyone who has not done so is unable to recognize what it is, or looks like.
Anyone who has realized the God in him has passed beyond any possibility of communicating his state to any who have not.
This is the paradox of awareness. You may - at great cost - attain it, but you will never be able, from that point on, to share it.
Jesus was as good an example as any, of what happens to those who try too hard, for too long.
And Christianity as good an example as any, of the long-term consequences of that tragic failure to communicate.