Hi, @RJM — really interesting question.
I'd like to work up some notes based on the metaphysics as set forth by René Guénon, with regard to 'the self' ... based on two key works: Man and His Becoming According to the Vedanta and The Multiple States of Being. As a side-note, a work entitled The Symbolism of the Cross forms a kind of blueprint along which his later writings developed.
Two key elements that have imprinted themselves on me are:
1] "The 'Self' is the transcendent and permanent principle of which the human state is only a transient and contingent modification.
2] "The Self" is not thereby affected, precisely because this process is only relative ... not a development at all, except from the point of view of manifestation, outside of which there is no question of succession, but only of perfect simultaneity, so that even what is virtual under one aspect, is found nevertheless to be realized in the 'eternal present'."
(Drawn from Man and His Becoming)
What strikes me is this idea of succession and simultaneity – something that is metaphysically undeniable, but is ignored by almost every exposition of a religious metaphysic. Its impact and meaning with regard to the distortion of the reality of 'hell' or 'reincarnation' that exists in the mind do so from the standpoint of setting out the other states of being according to our current state of ephemeral contingency, rather than the eternal and immutable.
The necessity of such the Buddhist refers to as an upaya ('an expedient means') and the Christian as 'pastoral care' — simply because most people are not metaphysicians, and need easier and more graphic concepts to grasp.
