Thematic Bible: Of the medes, irrevocable

Then the king, when he heard the word, was very much displeased with himself. And he set his heart on Daniel to deliver him. And he labored until sundown to deliver him. Then these men met before the king and said to the king, Know, O king, that the law of the Medes and Persians is that no ban nor law which the king establishes may be changed.