Was just thinking about this whole notion that Jesus was crucified between two thieves, and wondered why I’d never heard anybody give any kind of symbolic explanation as to why this was so. The first thing that comes to my mind is that they were trying to depict the fact that Christ himself really was a thief, but a thief of a different nature. What kind of thief? Well, my best guess would be the Christian concept of Ransom Theory, which says that Jesus’s death was basically a ransom paid to the devil so humanity would no longer be under his control. But God scoops Jesus back up to Heaven, thereby effectively using Jesus as an instrument to steal humanity back. Additionally, there is the Biblical reference to the return of the Son of Man as being like a “thief in the night.”

Also, I’m guessing there are probably pre-Christian mythological parallels as to why he was crucified between thieves. One site says that it was a modification of Mithras’s crucifixion story.

The Bible records that Jesus was crucified between two thieves. One went to heaven and the other to hell. In the Mithras mysteries, a common image showed Mithras flanked by two torchbearers, one on either side. One held a torch pointed upwards, the other downwards. This symbolized ascent to heaven or descent to hell.

Another site says that the Egyptian Horus was also crucified between two thieves, and that Jesus’s story and his match on a multitude of other points as well. Also, check out this excellent resource, Pagan Origins of the Christ Myth.

Lastly, I found this interesting metaphysical explanation of the two thieves motif:

We have all seen the traditional picture of the crucifixion with three crosses. Jesus on the one in the center ,and the two thieves crucified on either side. As the scripture says , they crucified two thieves with him, one on his left and one on his right.

We have established substantial evidence that the crucifixion occurs in the human skull at the place that Stedmans Medical dictionary refers to as calvaria or Mt Calvary which is the dome of the skull. What would qualify in the skull as the two thieves?

The eyes.! How many times have you said, “my eyes were deceiving me, or my eyes were fooling me”. The eyes take life away from us because we follow what we see with the two, yet we neglect following what we should,with the single eye .

Thus the two physical eyes represent the two thieves crucified on the left and right of Jesus, and He represents the center, or single eye, or Pineal Gland of the brain. Only once in the Bible is the single eye mentioned and it is mentioned by Jesus in Matthew 6:22 when he says, if your eye be single, your body will fill with light.

None of these explanations totally satisfies me, but it’s a step in the right direction.