I've heard from a friend a theory claiming Jonah died in the whale's belly and then he was raised from the dead to preach to the Ninevites. He told me it is based on those verses:
"He said: “In my distress I called to the Lord, and he answered me. From deep in the realm of the dead I called for help, and you listened to my cry." (Jonah 2:2, NIV)
"He answered, “A wicked and adulterous generation asks for a sign! But none will be given it except the sign of the prophet Jonah. For as Jonah was three days and three nights in the belly of a huge fish, so the Son of Man will be three days and three nights in the heart of the earth. The men of Nineveh will stand up at the judgment with this generation and condemn it; for they repented at the preaching of Jonah, and now something greater than Jonah is here." (Matthew 12:39:41, NIV)
I told him I don't agree with his theory because Jonah prayed inside the whale, but he was inflexible.
Also, here is an answer to raise this issue: Jonah and the Whale - Is there any scientific proof that it is possible to survive in the belly of whale?
I would especially like to hear answers from a Pentecostal perspective.