We have just seen that a person is either for Jesus or against Him. Many people, however, think they can sit on the fence. They neither curse Jesus as demonic nor worship Him. They reserve judgment until there is more evidence.

We meet such people in our passage today. They have already asked for a sign (v. 16), but Jesus calls them a wicked generation (v. 29). They have already been given many signs. The pagan people of Nineveh were not given any sign (except for Jonah, who served as a sign to them), and neither was the Queen of the South, yet the preaching of Jonah and the wisdom of Solomon were enough to produce faith in them. The power and authority of Jesus' words and works are far greater, so the demand for a sign is just another mark of their unbelieving hearts (vv. 29-32).

Jesus has taught the truth openly like someone who lights a lamp (v. 33). Why would you need more light when light is already flooding the room? If, though, your view of Jesus is warped, then you show yourself to be in spiritual darkness (vv. 35-36).

The battle with the religious leaders continues as Jesus denounces their hypocrisy. Jesus catalogues their failures as the teachers and leaders of God's people: they lack integrity because what you see on the outside does not match what is on the inside (vv. 39-41); they neither teach nor live out justice and mercy, which are at the heart of a godly life (v. 42); they crave the adulation of people (v. 43); they teach spiritual life but lead people into a spiritual graveyard (v. 44); and they make God's law an unbearable burden for people, without the comfort of grace (v. 46).

Most seriously of all, they stand in the tradition of their forefathers who opposed and murdered God's true messengers. What they did to the prophets, they now will do to the One who is greater than all the prophets combined (vv. 47-51).

There is a word here to Christian leaders: do not let your life and words become a barrier to people finding salvation, but let them be a bridge to Jesus instead (v. 52). There is a word to us all: walk with grace and humility, and remember that the only heart you should judge is your own.