Parable - a short, simple story designed to convey some religious principle, moral lesson, or general truth by comparison with actual events. A parable is often an allegory in which each character represents an abstract concept—such as obedience or honesty—and is illustrated through real-life events.
The term is from the Greek parabole, meaning “comparison” or “putting beside” which was derived from paraballein, meaning “to throw beside.”
Melville’s Billy Budd is sometimes offered as a parable since it demonstrates that absolute good may not co-exist with absolute evil. In this novel, Billy is an innocent, impressionable, young sailor, the personification of absolute good. He is court-martialed and hanged for mutiny and murder under trumped-up charges brought against him by Claggart, the personification of absolute evil.
see: allegory, fable