partly so - in this world, among the worldly ways, the temporal ruler has authority. However, the bargain is.. at birth, at death, in times of great peril, or any day when there are hungry, poor, afflicted, ill or outcast citizens (every day in other words) the temporal ruler has agreed to acknowledge One God (not the person ruling) and implement the words of the Christian canon .. to attend to those who are needy, sanctify marriage, watch over the helpless and bring food and medicine to those that need it.
In the modern times of post-industrial plenty, these crucial agreements are often overlooked. Yet this is how civilization grew from the barbarian times in the Western world.