Words are what feed the spirit, whether those words are merely in your own head or coming from a trusted source. The key would be what kind of spirit are you predisposed too. Doesn't I am the word and the light ring a bell?
So, in other words, words are the source of spiritual life? If so then spirituality is a matter of consciousness, the mind.
A mind living in accord with actual reality would be a mind living in the spiritual realm of the living. A mind living in denial of reality would be a mind living in the spiritual realm of the dead.
Nothing mysterious or mystical about that at all.