Daniel 6:12; Daniel 6:15

12 So they went to the king and spoke to him about his royal decree: “Did you not publish a decree that during the next thirty days anyone who prays to any god or human being except to you, Your Majesty, would be thrown into the lions’ den?” The king answered, “The decree stands—in accordance with the law of the Medes and Persians, which cannot be repealed.”

15 Then the men went as a group to King Darius and said to him, “Remember, Your Majesty, that according to the law of the Medes and Persians no decree or edict that the king issues can be changed.”