The Pharisees and some of the teachers of the law who had come from Jerusalem gathered around Jesus and
saw some of his disciples eating food with hands that were "unclean," that is, unwashed.
(The Pharisees and all the Jews do not eat unless they give their hands a ceremonial washing, holding to the tradition of the elders.
When they come from the marketplace they do not eat unless they wash. And they observe many other traditions, such as the washing of cups, pitchers and kettles. )
So the Pharisees and teachers of the law asked Jesus, "Why don't your disciples live according to the tradition of the elders instead of eating their food with 'unclean' hands?"
He replied, "Isaiah was right when he prophesied about you hypocrites; as it is written: " 'These people honor me with their lips, but their hearts are far from me.7They worship me in vain; their teachings are but rules taught by men.'8You have let go of the commands of God and are holding on to the traditions of men."9
And he said to them: "You have a fine way of setting aside the commands of God in order to observe your own traditions!10For Moses said, 'Honor your father and your mother,' and, 'Anyone who curses his father or mother must be put to death.'11But you say that if a man says to his father or mother: 'Whatever help you might otherwise have received from me is Corban' (that is, a gift devoted to God),12then you no longer let him do anything for his father or mother.13Thus you nullify the word of God by your tradition that you have handed down. And you do many things like that."