"And He said,"What comes out of a man, that defiles a man." Mark 7:20
Uncleanliness was a Jewish tradition. When people didn't comply with the purity laws, for example to wash their hands correctly before a meal, they were regarded as dirty or unclean. Jesus differed from this, Uncleanliness is something that lies in the heart, not the body. That is why we must allow Him to cleanse our soul. He can wash away the right kind of dirt from our hearts. He cleans us pure in the right ways.