It's pretty amazing that some of the common proverbs and expressions we use date back 2,000 or 3,000 years ago. Many come from ancient Greece and Rome, civilizations that were dominant and influential. Similarly, we borrow a lot of phrases from the Bible, the world's best-selling and most widely distributed tome, according to the Guinness Book of Records. Ancient fables also spawned innumerable expressions that have lasted through time, perhaps because they often include a memorable animal character who dispenses some bit of wisdom or practical advice [source: Horgan].
The following 10 common expressions all have intriguing back stories, starting with the tale of an immortal man with one mortal body part.