Daniel 6:10, 15

When Daniel knew that the document had been signed, he went to his house where he had windows in his upper chamber open toward Jerusalem. He got down on his knees three times a day and prayed and gave thanks before his God, as he had done previously.

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