The sign of Jonah (Matthew 12:39)—Jonah’s three days and three nights in the belly of the fish—will show Jesus as the Messiah when he rises from the dead. This is the second time that Jesus says that he will be raised following his death (the first time, see John 2:19). Although the leaders will try to remove Jesus from the people through a trial, he will remain the sign for Israel through the preaching of judgment by the Son of Man. As Jonah was absent for only a short time, the Son of Man will be absent for only a few days. After that, God will continue to confront them through Jesus. Matthew 12:40 thus not only describes the sign of Jonah, but stresses how this hostile generation cannot escape the God-given sign of the Son of Man
The sign of Jonah (Matthew 12:39) will legitimize Jesus as the Messiah when he rises from the dead. In Matthew 12:40, where Jesus refers to Jonah’s three days and three nights in the belly of the fish it was the second time that Jesus announced that he would be resurrected following his death (the first time, see John 2:19).1
The Son of Man will be pushed out of public life in Israel, and the leaders will attempt to remove him from the people by means of a trial. Yet Jesus will remain the sign for Israel through his preaching of judgment by the Son of Man. The authorities can silence him for only three days and three nights. After that, God continues to confront them through Jesus. People are only able to get rid of him for only a moment, but they cannot escape him. The Pharisees desire to cast Jesus’ corpse into the grave, but not even that will not eliminate God’s sign for this generation. Jonah was absent for only a short time, and so too the Son of Man will be absent for only a few days. The plans of the Pharisees to rid themselves of him, will only lead to them being confronted by him even more emphatically. As such Matthew 12:40 not only describes the sign of Jonah, but highlights the development of the idea that this hostile generation cannot escape the God-given sign of the Son of Man.2
40 For just as Jonah was three days and three nights in the belly of the great fish, so will the Son of Man be three days and three nights in the heart of the earth.