Digging in to the Gospel tradition

Luke 17: 11-19 This account shows how a leper and legally observant Jesus should behave.
Contrast this with Mark 1:40-44 (read in the B cycle for the 6th Sunday of the year).
from John Crossan, Jesus, p. 83
"In terms of the original situation, Jesus' action puts him on a direct collision course with priestly authority in the Temple. After touching a leper he can hardly turn around and tell him to observe the purity code that he himself has just broken.
But what we see at the transmissional level is intense apologetics seeking to bring Jesus into line with traditional biblical and legal practice--to show him, in terms of purity regulations, as an observant Jew,....especially that terminal injunction in 1:44 to "go show yourself to the priest, and offer for your cleansing what Moses commanded."
Finally, at the third or redactional level, as Mark records the story in his gospel, he makes one very significant final change. He himself is much more in sympathy with that legally unobservant Jesus at the story's original level, so he adds, after the injunction to go to the Temple, a phrase translated as "as a testimony to them." It could be better translated with, "as a witness against them"--in other words, "to show them who's boss." But in either case, for Mark, Jesus is enjoining the visit to the Temple not as legal observance but as confrontational witness."