The first Wednesday in Lent, so called from an ancient Roman
Catholic custom of sprinkling ashes on the heads of those
condemned to do penance on this day. The ashes were those of the
palms burnt on Palm Sunday. The pessimi were sprinkled with
ashes, the less offending were signed on the forehead with the
sign of the cross, the officiating minister saying, “Memento,
homo, quia pulvis es, et in pulverem reverteris.” The custom,
it, is said, was introduced by Gregory the Great. Source:
Dictionary of Phrase and Fable, E. Cobham Brewer, 1894 More on
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