“One key—probably the most important one—to Charlemagne’s political thought is Augustine’s City of God, which, next to the Bible, was his favorite book. In reflecting on the temporal and heavenly realms, the patriarch took issue with ascetics who urged withdrawal from fallen human society in pursuit of an attainable holiness. He pointed out that perfection is impossible in this world, where divine and satanic forces are locked in constant conflict. The only sinless society will be that which gathers around the throne of God at the end of time. The moral for the leaders of both Church and state was not withdrawal, or even the establishment of monasteries as gateways to perfection, but earnest engagement in the battle against the forces of evil.
It followed from this that territorial boundaries were of little spiritual consequence. No ruler could create a truly “Christian” empire, within whose bounds truth and purity would prevail and beyond which lie unredeemed humanity and the chaos of unbelief. Moreover, his thoughts and aspirations should be focused on the New Jerusalem and on assuring himself of a place among its citizenry. To achieve that desired objective he had to shoulder the solemn responsibility of drawing his people ever closer to the ideal of the heavenly city. That involved scrupulous attention to divine “order” in the life of Church and state.
Derek Wilson, Charlemagne (New York: Doubleday, 2006), 128-9.
Short Stories on Honor, Chivalry, and the World of Nobility—no. 324