Luke 11:29-32

As the crowds were increasing, Jesus began to say, “This generation is a wicked generation; it looks for a sign, but no sign will be given to it except the sign of Jonah. For just as Jonah became a sign to the people of Nineveh, so the Son of Man will be a sign to this generation. The queen of the South will rise up at the judgment with the people of this generation and condemn them, because she came from the ends of the earth to hear the wisdom of Solomon—and now, something greater than Solomon is here! The people of Nineveh will stand up at the judgment with this generation and condemn it, because they repented when Jonah preached to them—and now, something greater than Jonah is here!

Jonah 3 describes of when Jonah preached against Ninevah. Jonah 3:4-5 says, “Jonah began by going a day’s journey into the city, proclaiming, ‘Forty more days and Nineveh will be overthrown.’ The Ninevites believed God. A fast was proclaimed, and all of them, from the greatest to the least, put on sackcloth.” Not only this, but the king decrees that everyone stop their evil ways and violence in hopes that God will relent and not destroy them. Ninevah heard the warning and changed. Once they recognized that they were doing evil, they tried to stop that and instead urgently called upon God. Jesus’ message is similar, “Repent, for the kingdom of heaven is at hand!” Unfortunately, the Jewish leadership didn't see the warning from Jesus like Ninevah saw the warning from Jonah.