What does Matthew 12:42 mean?
Jesus has called this generation of Israelites evil and spiritually adulterous. They have failed to repent despite His preaching about the kingdom of heaven and despite all the displays of power they have seen in Him. Some believed Him to be the Messiah and repented in preparation for His kingdom; most Israelites did not believe or declare their faith in Him (Matthew 12:38–41).Jesus has refused to give them any immediate miraculous sign to prove Himself. However, He has predicted a supernatural event which they ought to recognize when it happens. As Jonah was in the belly of the huge fish for three days (Jonah 1:15–17; 2:10), Christ, the Son of Man, will be in the heart of the earth for three days. At this time, Jesus did not elaborate, but He was describing His own death and miraculous resurrection (John 2:19–22).
Part of the criticism Jesus levels against His peers is that even wicked, pagan nations like Nineveh were willing to repent when they heard a message from God. Even the king of the wicked city repented when Jonah finally came to preach about God's judgment. Jesus implies that when all men are eternally judged, in the end times, the people of Nineveh will have every right to condemn that generation of Israelites for their unbelief and unrepentance.
The queen of the South is also known as the Queen of Sheba. She heard about the wisdom of Solomon and the splendor of Israel under his rule and traveled great distances to see it with her own eyes (1 Kings 10:1–29). Jesus now says that something greater than Solomon is here, meaning Himself as the Messiah. The Queen of Sheba traveled all the way to Israel to hear Solomon. In contrast, this generation of Israelites would not even receive the Messiah—far greater than any other king—when He appeared in person and performed miracles right in front of them (Matthew 12:9–13; 22)!
Jesus has now declared Himself to be greater than the temple (Matthew 12:6), greater than the prophet Jonah (Matthew 12:41), and greater than King Solomon. His words and deeds proved this to be true, as did the prophecies of Scripture (John 5:39–40). Still, the Israelites of His day would not believe.