Other mistake: When the Pirates are arrested in Nineveh, another soldier walks up to Jonah and knocks him out with a fish. When this happens, Jonah is wearing the Cheese Curl hat. When he comes to on the Slap of No Return, he is wearing his turban again. Would the soldiers change his hat?
Trivia: In the biblical book of Jonah, there is actually no whale that swallowed Jonah. The "whale" is a mistranslation of the Hebrew word for a big fish by the translators of the King James Version. Because of the prominence, respectability, and the wide distribution (it is in the public domain in the U.S., but not in the U.K.) of the King James translation over modern translations like the New International Version, the "whale" is what most Bible readers think of the sea creature that swallowed Jonah.