There is profound misunderstanding in many circles concerning the issues of "clean" and "unclean" - and out of that misunderstanding comes many false theologies. The fact that Yeshua "put on flesh" and became subject to death is seen not only in His atoning work, but also in His life, both then and now. "Leprosy" is seen as the ultimate expression of the frailty of humanity – stopping just short of death. It is the "walking death" – the nearly the worst in "clean" versus "unclean" with only death itself being more defiling. And yet Yeshua identifies with the leper. He touches him. He heals him. This is the mark of Messiah: Who bravely goes to those afflicted with "death" and cares for them… and heals them.

An account in the Talmud speaks to this as well. Rabbi Joshua ben Levi, was a Third Century teacher who is said to have had an encounter with Elijah (not uncommon in the Talmud). Rabbi Joshua asks Elijah,

"When will the Messiah come?" - "Go and ask him himself," was his reply. "Where is he sitting?" - "At the entrance." "And by what sign may I recognize him?" - "He is sitting among the poor lepers [caring for them]... 

So he went to him [Messiah] and greeted him, saying, "Peace upon thee, Master and Teacher."  "Peace upon thee, O son of Levi," he replied. "When wilt thou come Master?" asked he, "Today," was his answer. On his returning to Elijah, the latter enquired, "What did he say to thee?"... "He spoke falsely to me," he rejoined, "stating that he would come today, but has not." He [Elijah] answered him, "This is what he said to thee, today, if ye will hear his voice."
 b.Sanhedrin 98a (Soncino edition)

With echoes of Psalms 95:7ff, and by extension Hebrews 4:7ff, we hear the challenge of the "Leper Messiah" - do you hear His voice? He came and sat among us, we lepers. He bound up our sores. He healed us from our "death" disease. Do you hear the "Leper Messiah"? He is coming today.