For as Jonas was a sign unto the Ninevites, so shall also the Son of man be to this generation.
Luke 24:46
and He said to them, "Thus it is written, that the Christ would suffer and rise again from the dead the third day,
Luke 24:47
and that repentance for forgiveness of sins would be proclaimed in His name to all the nations, beginning from Jerusalem.
Jonah 1:17
And the LORD appointed a great fish to swallow Jonah, and Jonah was in the stomach of the fish three days and three nights.
Jonah 2:10
Then the LORD commanded the fish, and it vomited Jonah up onto the dry land.
Jonah 3:2-10
2
"Arise, go to Nineveh the great city and proclaim to it the proclamation which I am going to tell you."
3
So Jonah arose and went to Nineveh according to the word of the LORD. Now Nineveh was an exceedingly great city, a three days' walk.
4
Then Jonah began to go through the city one day's walk; and he cried out and said, "Yet forty days and Nineveh will be overthrown."
5
Then the people of Nineveh believed in God; and they called a fast and put on sackcloth from the greatest to the least of them.
6
When the word reached the king of Nineveh, he arose from his throne, laid aside his robe from him, covered [himself] with sackcloth and sat on the ashes.
7
He issued a proclamation and it said, "In Nineveh by the decree of the king and his nobles: Do not let man, beast, herd, or flock taste a thing. Do not let them eat or drink water.
8
"But both man and beast must be covered with sackcloth; and let men call on God earnestly that each may turn from his wicked way and from the violence which is in his hands.
9
"Who knows, God may turn and relent and withdraw His burning anger so that we will not perish."
10
When God saw their deeds, that they turned from their wicked way, then God relented concerning the calamity which He had declared He would bring upon them. And He did not do [it].
Matthew 12:40-42
40
for just as JONAH WAS THREE DAYS AND THREE NIGHTS IN THE BELLY OF THE SEA MONSTER, so will the Son of Man be three days and three nights in the heart of the earth.
41
"The men of Nineveh will stand up with this generation at the judgment, and will condemn it because they repented at the preaching of Jonah; and behold, something greater than Jonah is here.
42
"[The] Queen of [the] South will rise up with this generation at the judgment and will condemn it, because she came from the ends of the earth to hear the wisdom of Solomon; and behold, something greater than Solomon is here.