E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Al Aswad, who set himself up as a prophet against Mahomet. He was called the Weathercock because he changed his creed so often, the Impostor, and the Liar.
Moseilma, another contemporary, who affirmed that the belly is the seat of the soul. He wrote to Mahomet, and began his letter: From Moseilma, prophet of Allah, to Mahomet, prophet of Allah, and received for answer a letter beginning thus: From Mahomet the prophet of God, to Moseilma the Liar. (Anglo-Saxon, leg-an, to tell a falsehood; but to be recumbent is lieg-an or lig-an.)
Prince of Liars. Ferdinand Mendez Pinto, a Portuguese traveller, whose narrative is so much after Munchausens style, that Cervantes dubbed him Prince of Liars. The Tatler called him a man of infinite adventure and unbounded imagination.