Cross reference
Luke 11:38
38 And when the Pharisee saw it, he marvelled that he had not first bathed himself before dinner.
Matthew 15:2-3
2 Why do thy disciples transgress the tradition of the elders? for they wash not their hands when they eat bread.
3 And he answered and said unto them, Why do ye also transgress the commandment of God because of your tradition?
Mark 7:2-5
2 and had seen that some of his disciples ate their bread with defiled, that is, unwashen, hands.
3 (For the Pharisees, and all the Jews, except they wash their hands diligently, eat not, holding the tradition of the elders;
4 and `when they come' from the market-place, except they bathe themselves, they eat not; and many other things there are, which they have received to hold, washings of cups, and pots, and brasen vessels.)
5 And the Pharisees and the scribes ask him, Why walk not thy disciples according to the tradition of the elders, but eat their bread with defiled hands?
John 3:25
25 There arose therefore a questioning on the part of John's disciples with a Jew about purifying.