Jonah was swallowed by a great fish in the Old Testament. The episode appears in the Book of Jonah, where the prophet is thrown overboard during a storm and the Lord appoints a great fish to swallow him.
Jonah remains inside the fish for three days and three nights. He prays, and the fish eventually vomits him onto dry land. The story then returns to Jonah's original mission: preaching to the people of Nineveh, a major city traditionally associated with the Assyrian Empire.
Many paintings, stories, and films identify the creature as a whale, but the biblical text does not name a species. It says only “great fish.” The New Testament later refers to Jonah's three days in the fish when discussing the sign of Jonah, which is why the story is important in both Jewish and Christian tradition.