Mark 7:3-5
3 (The Pharisees and all the Jews do not eat unless they give their hands a ceremonial washing, holding to the tradition of the elders.
4 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.)
5 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?”