In Mark 7:1-16, Jesus’ disciples eat their food without performing a ritual purification of their hands and the Pharisees take the opportunity to challenge Jesus’ honour.
“What kind of teacher can he be if his disciples transgress the revered “tradition of the elders” (that was attaining a status equal to the written Torah)? Jesus responds … with a counterchallenge. He challenges the Pharisees’ honor as followers of Torah, citing an instance where their tradition stands in contradiction to the written Torah (7:9-13), indeed, one of the Ten Commandments, allowing him even to apply a devastating quotation from Isaiah in his riposte. (7:6-7)”
David deSilva comments that “the reader is reminded of the public nature of this exchange as Jesus addresses his last comment to the crowd (Mark 7:16). Presumably Jesus has successfully warded off the challenge and even caused his opponents to lose face with the counterchallenge. In telling these stories, moreover, the Gospel writers make the Christian readers into the public that witnesses the exchanges and gives its own verdict on who won and who lost. Their own positive estimation of Jesus (as an honorable person and as a reliable teacher of the way to please God) is confirmed as they read these challenge-riposte stories actively and appraisingly.”