The view of the unknown poet is that two thieves represent two different ways of appreciating our common humanity. In particular, one should look at his "Ballad of a Robber and a Thief".
That said, the unknown poet reveals one again in his notes to this verse his intense distaste for what he calls "religious flimflam" which he "...abhor[s] with a purple passion". He continues:
"When it all comes down to dust, we all must go through that door into the long night with no one, alone and forsaken. If it were not so, then life itself would have no real meaning -- and life without meaning is hell. That is the grit of being spiritual. There is absolutely no way to separate the spiritual from the physical and it is a grave mistake to even try."
Speaking as a robber and a thief,
can anyone explain the sources of our belief?
These confused remains of memory,
are they some sort of help before eternity?
Do I have the right to anything
when I forget the simple source of human being?
Our ship has sprung a monstrous leak,
can we be sure she'll stay afloat another week?
What has done has not been hid.
To looks inside the can, you have to take off the lid.
It's a fact that less than just a few
can stand the sight of all that pure, tomato-juice!
So, blow your nose, wipe away the snot!
Johnny Wayne's brand of Calvary are not
agonna save you from your thrill.
That, dear friend, is the grit of being spiritual!...