The last verse of the first chapter of Mark says that this ex-leper was to blame for news about Jesus to spread everywhere, keeping Jesus out of populated areas. In the very next verse, Jesus is back in Capernaum, so was not so limited in movement as this verse would propose. Not to mention that Jesus had already been generating some large crowds without this leper’s help, so this seems an unlikely explanation and a bizarre insertion.
In these three verses, we see a Jesus who is suddenly disinterested in publicity, unwilling to be identified, and suddenly very interested in obscure Temple rites. Is this even the same guy as the one from verses 9-39 who seemed to rejoice in great crowds and was unashamed to heal the sick? Joshua/Jesus was a relatively common name: was this just some other Jesus that someone mistook for Jesus of Gamla?
The biggest difference between Jesus of verses 9-39 and the one in 40-45 is that the latter Jesus seems to be lacking in authority. None of the prior people healed by Jesus in verses 30-39 were told to see the priest, none were told to be quiet about their healing. Jesus didn’t appear to be ashamed or cowed by those he had healed prior to meeting the leper. But here, he suddenly appears unsure about his authority, suggesting that a priest would be needed to validate his work, and not wanting people to know he had been responsible. The fact that he spelled out specific instructions that the leper ignored seems like another hit to Jesus’ authority.
If we suppose that “leprosy” was, like demon possession and “illness”, another euphemism for political opposition to Rome, perhaps this was meant to refer to a specific person – perhaps someone who famously had leprosy – and this was meant to say that this person, too, eventually saw the light of the Rightness of Rome. Perhaps these six verses were added later, after the image of Jesus had changed for believers.
One weird connection to be considered here is that the leper in verses 40-46 might have been a late insertion into the chapter: a reference to Paul as “unclean” to toss a dig at the evangelist who famously reinterpreted the Gospel. Leprosy – as a form of uncleanliness – could have been meant to reference those who actively persecuted Christians, such as Paul was said to do prior to “seeing the light”.
The way I’m going with this passage is that the Jesus of verses 40-46 is not the same guy as Jesus from 9-39, at the very least, it’s not from the same hand. Instead, mistaken identity means that there are now at least two people named Jesus that folks are identifying as the one with authority. Unless I can narrow down the identity of the leper, I’m not sure I can understand this passage any better.