The Wolf in Sheep’s Clothing (Perry Index 451) is one of Aesop’s most widely quoted fables and the origin of the English idiom "a wolf in sheep’s clothing." The phrase also appears in the Bible (Matthew 7:15), where Jesus warns: "Beware of false prophets, which come to you in sheep’s clothing, but inwardly they are ravening wolves." Whether the biblical usage influenced later tellings of the fable, or vice versa, has been debated by scholars for centuries. The fable appears in numerous classical collections and was retold by Jean de La Fontaine in his Fables (1668).

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