Daniel 6:10, 15

Now when Daniel knew that the document was signed, he entered his house (now in his roof chamber he had windows open toward Jerusalem); and he continued kneeling on his knees three times a day, praying and giving thanks before his God, as he had been doing previously.

Then these men came by agreement to the king and said to the king, “Recognize, O king, that it is a law of the Medes and Persians that no injunction or statute which the king establishes may be changed.”