Bible Verses About Medo-Persian Kingdom: Laws of, unalterable

So they went to remind the king of his royal decree: "Didn't you sign a law prohibiting anyone from making requests of any god or man within thirty days, except yourself, your majesty, on pain of being thrown into the lion pit?"The king answered, "Yes, that is true, as required by the law of the Medes and Persians, which is itself irrevocable."

But these men descended on the king and said to him, "Remember, your majesty, that it is a law of the Medes and Persians that no decree or edict, once issued by the king, can be revoked."