For word came unto the king of Nineveh, and he arose from his throne, and he laid his robe from him, and covered himself with sackcloth, and sat in ashes.
All Commentaries on Jonah 3:6 Go To Jonah 3
Augustine of Hippo
AD 430
A king serves God one way as a man, another as a king. He serves him as a man by living according to faith. He serves Him as king by exerting the necessary strength to sanction laws that command goodness and prohibit its opposite. The king of the Ninevites served God by compelling the whole city to appease the Lord.