Matthew 12:38-41

Then certain of the scribes and Pharisees answered him, saying, Teacher, we would see a sign from thee. But he answered and said unto them, An evil and adulterous generation seeketh after a sign; and there shall no sign be given to it but the sign of Jonah the prophet: for as Jonah was three days and three nights in the belly of the whale; so shall the Son of man be three days and three nights in the heart of the earth. The men of Nineveh shall stand up in the judgment with this generation, and shall condemn it: for they repented at the preaching of Jonah; and behold, a greater than Jonah is here.