Dan Daniel, chapter Book of Daniel, chapter 6
Then they came near, and spoke before the king concerning the king's interdict: 'Hast thou not signed an interdict, that every man that shall make petition unto any god or man within thirty days, save of thee, O king, shall be cast into the den of lions?' The king answered and said: 'The thing is true, according to the law of the Medes and Persians, which altereth not.'