A lad, a garcon, a servant. (Anglo-Saxon, cnáfa; German, knabe.) The knave of clubs, etc., is the son or servant of the king and queen thereof. In an old version of the Bible we read: “Paul, a knave of Jesus Christ, called to be an apostle,” etc. (Rom. i. 1).
This version, we are told, is in the Harlelan Library, but is generally supposed to be a forgery. But, without doubt, Wycliff (Rev. xii. 5, 13) used the compound “Knave-child,” and Chaucer uses the same in the Man of Lawe's Tale, line 5130.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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