Once more, Jesus is asked to prove his authority by doing tricks. Once more, he refuses to be defined by his miracles. Then he goes further: he commends the people of Ninevah and the Queen of Sheba, two stories from the Hebrew scriptures that commend those outside the chosen people of Israel for their faith. This must have stung, but it was appropriate. Ninevah showed repentance, and the queen showed respect. Neither of those things were shown to Jesus by God's chosen insiders, and Jesus wasn't letting them off the hook without knowing it.