“Is it lawful for a man to put away his wife for every cause?” The last three words are the point. The two great Pharisaic teaching schools of the generation before Jesus, the houses of Hillel and Shammai, disagreed on record over the divorce grounds in Deuteronomy 24:1: Shammai's house allowed divorce only for unchastity, Hillel's house “even if she spoiled his dish,” and Rabbi Akiva later added “even if he found another fairer than she” (the Mishnah preserves all three positions, Gittin 9:10). “For any cause” is the Hillelite slogan. The questioners are asking Jesus, in Herod Antipas's territory where John the Baptist lost his head over a marriage, to take a side in a live intra-Pharisaic dispute.

Jesus declines the menu. He reaches behind Moses to creation (“from the beginning it was not so”), grounds marriage in Genesis 1:27 and 2:24, reads the Mosaic provision as concession to hard hearts, and lands nearer Shammai on the exception while resting the whole matter on ground neither school had made primary. The scene is only half understood until the reader knows there were two schools in the room.