Esther 1:19

After these things when the wrath of King Ahasuerus had subsided, he remembered Vashti and what she had done and what had been decided against her.

“Now you write to the Jews, according to what is good in your eyes, in the king’s name, and seal it with the king’s signet ring; for a written decree which is written in the name of the king and sealed with the king’s signet ring may not be turned back.”

“Now, O king, establish the injunction and sign the written document so that it may not be changed, according to the law of the Medes and Persians, which may not be revoked.”

Then they came near and said before the king concerning the king’s injunction, “Did you not sign an injunction that any man who seeks to make a petition to any god or man besides you, O king, for thirty days, is to be cast into the lions’ den?” The king answered and said, “The word is certain, according to the law of the Medes and Persians, which may not be revoked.”