ISB ~ Luke 5 v13

touched him:It was unthinkable for a Jew to touch a leprous outcast.

Jesus nevertheless crosses this boundary and reverses the expected outcome:instead of contracting ritual uncleanness himself, he cleanses the leper of his ailment by the very act of touching him. This shows that Jesus brings into the world a new form of holiness that overpowers even defilement and disease. See note on Mt 8:1-9:38.