This proverb is about a general under King Chén of the Southern Dynasty. King Chén cared nothing for ruling his country, and instead spent his days in pursuit of pleasure.

The general, whose name was Xú Dé Yán, felt his country was in grave danger because of the king’s behavior. And if there was a war, he would most likely be separated from his wife.

So he took a round mirror and broke it in half, giving one piece to his wife and keeping the other for himself. He told her that if they were separated, they could use the pieces of the mirror to recognize each other. They agreed to search for each other every year on Lantern Festival, when they would go to the market to sell mirrors.

It came to pass that the kingdom was attacked, and Xú Dé Yán and his wife were separated. They kept searching for each other, though, and eventually were reunited.

This proverb is said of a couple which has separated for any reason, but finally got back together.
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