It's well documented that the practice of blessing someone after a sneeze is (at least anecdotally) due to a belief that the soul leaves the body during a sneeze.

There is also a prayer in the Jewish liturgy that thanks God for the return of the soul to the body.

However, after on a journey where one's body (and therefore one's ego) is separated from one's soul, how can we tell with any certainty that the soul that returns is really the same soul that left?

At no time was this question more pressing to me than after a big bowl of salvia. The loss of identity that comes along with that smoke gave me a sense of my ego burning away.

Who what where and when am I? How old am I? How come I have any sense of indexicality with no inkling of self?

And then that feeling of being pulled back into nothingness and fighting against it and all the while wondering why. And only now, once again coalesced into one piece, do I realize that what I fear most about Buddhism, nirvana and egolessness is that nagging fear that escaping from the circle of samsara amounts to nothing but death.