It was shared with me at one point in my life that to be a disciple means to walk so closely to the master that the dust of the masters that is kicked up can fall upon the disciple.
To be a disciple of Jesus means to be that close - so the dust will fall upon you.
This takes a few things to consider that are interesting.
Crowds that press upon Jesus so closely are often described as desiring to be healed. But maybe they desired the dust of the "Second Adam" to fall upon them?
When Jesus encourages the seventy (or seventy-two) to go out to the outer towns, and they are not welcomed they are told to shake the dust off their shoes. A friend pointed out that maybe in shaking the dust off their shoes also means that the dust that came off of Jesus is left in that town.
Just a couple observations, but stuff I found interesting.