Every culture has a mark of defilement, a way of distinguishing the deplorable from the righteous. We may define this with religion, ethics, knowledege, family name, or social status. In Jesus' day it was no different, but their defining matrix, the tradition of the elders, was elevated on the same authority as God's Word. For those who worship the One True God there is no other authority than God's revelatory Word. Mark shows us that Jesus is the final authority and it is was He tells us that should define our understanding of what is defiled in the eyes of the Father.