DELUGE, n. A notable first experiment in baptism which washed away the sins (and sinners) of the world.

Ambrose Bierce (1842-1914?) American writer and journalist

“Deluge,” The Cynic’s Word Book (1906)
    (Source)

Included in The Devil's Dictionary (1911). Originally published in the "Devil's Dictionary" column in the San Francisco Wasp (1882-01-20).

The original Wasp entry included a second sentence: "Since then it has been deemed advisable to let the sinners remain on their good behavior."