When you die and go to heaven, or the other place, your body is left behind to rot.  That frees you up for an eternity of new experiences; unless you believe in reincarnation, once you’re gone you’re gone.  In Dick’s The Three Stigmata Of Palmer Eldritch, reality as usual, becomes much more complicated.  The two competing hallucinatory drugs, Can-D and Chew-Z, both send the user into alternate realities.  Use Can-D and you ‘become’ a character back on Earth, whose experiences depend on how much of the associated accessories you have purchased.  Your body stays put, and you return to it with the usual drug after effects.  Chew-Z is much more like getting lost in a hall of mirrors, sending you into ever deeper layers from which you may or may not return, one level at a time.  But that’s the religious issue!  If you don’t return, do you exist in Chew-Z land for eternity?  As Dick says, “you got what St. Paul promises … you’re no longer clothed in a perishable, fleshly body – you’ve put on an ethereal body in its place.”  That is but one of many interesting religious themes in The Three Stigmata Of Palmer Eldritch.  Read it over and over again, and get lost in its many layers!