Augustine of Hippo

How, then, do kings serve the Lord with fear except by forbidding and restraining with religious severity all acts committed against the commandments of the Lord? A sovereign serves God one way as man, another way as king: he serves him as 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. It was thus that Hezekiah served him by destroying the groves and temples of idols and the high places that had been set up contrary to the commandments of God; thus Josiah served him by performing similar acts; thus the king of the Ninevites served him by compelling the whole city to appease the Lord; thus Darius served him by giving Daniel power to break the idol and by feeding his enemies to the lions; thus Nebuchanezzar … served him when he restrained all his subjects from blaspheming God by a terrible penalty. It is thus that kings serve the Lord as kings when they perform acts in his service that none but kings can perform.