Thematic Bible: Decrees of, irrevocable

Also, concerning the Jews, write as you see fit, in the king’s name, and seal it with the king’s signet ring—for a decree which is written in the king’s name and sealed with the king’s signet ring may not be revoked.” Verse ConceptsSealing The Message

Then they came near and said before the king concerning his prohibitory decree, Have you not signed an edict that any man who shall make a petition to any god or man within thirty days, except of you, 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king answered and said, The thing is true, according to the law of the Medes and Persians, which cannot be changed or repealed. Then they said before the king, That Daniel, who is one of the exiles from Judah, does not regard or pay any attention to you, O king, or to the decree that you have signed, but makes his petition three times a day. Then the king, when he heard these words, was much distressed [over what he had done] and set his mind on Daniel to deliver him; and he labored until the sun went down to rescue him. read more.
Then these same men came thronging [by agreement] to the king and said, Know, O king, that it is a law of the Medes and Persians that no decree or statute which the king establishes may be changed or repealed.

Now, O king, establish the decree and sign the writing that it may not be changed, according to the law of the Medes and Persians, which cannot be altered. So King Darius signed the writing and the decree.