The way we access spiritual information could very possibly be a poorly developed sense organ, akin to the earliest precursor of the eye - perhaps a cell that just barely registered some biochemical change when the light level impinging on it changed radically.

Since it so rudimentary it cannot clearly delineate what it "sees" but it knows there is something there and reports this to the rest of the mind. Perhaps it can be "tuned", much as a crude sense of pitch can be refined by practice and experience. It is almost certainly a bit variable in its sensitivity from person to person.

This organ (humor the theory at least for the time it takes to read this piece...) may seem to be unlike our other organs, at least at first. Perhaps it is little more than some odd organisation of the brain tissue that acts as (pathetic metaphor) an antenna for some kind of information.

But what was the primitve eye? Even less, I suspect.

If you consider the physical senses carefully, they seem to consist of some sorts of specialised cells that at some point very close to the organ itself are intimately connected to nerves leading straight into the brain. Since it would be pointless (and hence not a survival advantage) to develop a physical sense organ inside the brain, of course the five senses are all "remote" to the brain - held outside the brain by specialised structures, but still really a directly reporting subunit of it.

If a developing organ, however, does not need to "see outside" the brain, but is able to do whatever function it does quite comfortably from inside a mass of nerve tissue, it will not gradually "protrude" to as to work better.

I realise this line of reasoning runs into some fundamental issues when I try to ascertain what it is that the organ is "sensing" - I am getting close to saying it is a physical property of matter/energy, and as such somehow its qualities should be measureable, and the act of stimulating the brain, or being "received" by it, must surely affect some sort of energy level in the source.