The one sign
The Pharisees came to Jesus and demanded proof. He gave them one answer:
"An evil and adulterous generation seeketh for a sign: and a sign shall not be given it, but the sign of Jonas, the prophet. For as Jonas was in the whale's belly three days and three nights: so shall the Son of man be in the heart of the earth three days and three nights."
Matthew 12:39 to 40
Out of everything in the Old Testament, this is the one Jesus chose to stake his name on.
Down into the deep
God sent Jonah to preach to Nineveh, the capital of Assyria, Israel's enemy. Jonah ran the other way. A storm hit his ship, and the sailors threw him overboard to save themselves.
"Now the Lord prepared a great fish to swallow up Jonas: and Jonas was in the belly of the fish three days and three nights."
Jonas (Jonah) 2:1 ยท around 760 BC
Jonas is the Douay-Rheims spelling of Jonah. In most Bibles this verse is Jonah 1:17.
Out of the belly of hell
Listen to how Jonah describes where he was:
"I cried out of my affliction to the Lord, and he heard me: I cried out of the belly of hell, and thou hast heard my voice."
Jonas (Jonah) 2:3
He calls it the belly of hell, the place of the dead. One man goes down to save the others on the ship, descends into death, and on the third day comes back up:
"And the Lord spoke to the fish: and it vomited out Jonas upon the dry land."
Jonas (Jonah) 2:11
Then the nations believe
Jonah finally went to Nineveh. The most brutal empire of its day heard him and repented:
"And the men of Ninive believed in God: and they proclaimed a fast, and put on sackcloth from the greatest to the least."
Jonas (Jonah) 3:5
A pagan city, Israel's enemy, turned to God after the prophet came back from the dead. After the resurrection, the message of Jesus went out to every nation in the same way.
Jesus said it himself: "The men of Ninive shall rise in judgment with this generation... And behold a greater than Jonas is here" (Matthew 12:41).
Why this is a big deal
Jesus could have pointed to any of his miracles. He pointed to his own death and resurrection, and to a prophet who had acted it out nearly eight centuries earlier.
Three days down. Then back up alive. Then the whole world.