Prophet Yunus was instructed by Allah to warn the people of Nineveh of their sinful ways. However, Yunus tried to flee from this task and boarded a ship. During the journey, he was thrown overboard by the crew during a storm, and was swallowed by a large fish (often depicted as a whale).

While inside the fish, Yunus prayed to Allah for forgiveness and was miraculously saved after three days. He was spat out by the fish and went on to complete his mission, successfully warning the people of Nineveh and leading them to repentance.

This story is mentioned in the Quran, Surah Al-Anbiya', verses 87-88, and is a symbol of Allah's mercy, forgiveness, and the importance of obeying His commands.

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