Where did the saying writing on the wall come from?

The saying "writing on the wall" originates from the biblical story in the Book of Daniel, where mysterious handwriting appears on a wall during a feast hosted by King Belshazzar of Babylon. The writing is interpreted by the prophet Daniel as a divine message indicating the king's impending doom and the fall of his kingdom. Over time, the phrase has come to symbolize an ominous indication of future misfortune or inevitable failure.