The Pharisaic program was a table program. A chaver (“associate,” a member of the fellowship) undertook to eat only properly tithed, ritually pure food, and therefore would not accept the hospitality of an am ha'aretz (“people of the land,” the ordinary non-observant), whose food and vessels could not be trusted; the Mishnah sets out those membership terms (Demai 2:2). Tax collectors stood lower still: collaborators living by extortion, so far outside the community's trust that the Mishnah rules a house unclean if tax collectors have entered it (Taharot 7:6). Reclining at Matthew's table was therefore not loose etiquette; it was a deliberate crossing of a purity-and-loyalty boundary, and Jesus defends it from the prophets: “I desire mercy, and not sacrifice” (Hosea 6:6).

The fasting question that follows comes from devout practice, not hostility: John's own disciples fasted. The Torah commands one fast a year (the Day of Atonement); the pious added voluntary fasts, by Jesus' day typically Monday and Thursday, a rhythm the Talmud's fasting tractate discusses (Ta'anit 12a) and the Pharisee of Luke 18:12 names: “I fast twice in the week.” Jesus' answer runs on the tradition's own wedding law: a bridegroom is exempt from reciting the Shema on his wedding night, because joy overrides (Mishnah Berakhot 2:5). “Can the wedding guests mourn while the bridegroom is with them?” claims that exemption for His whole company, and quietly takes the Bridegroom's role, which in the Prophets belongs to God Himself (Hosea 2, Isaiah 62:5).