Without altering the boundaries

For, without altering the boundaries of the empire, Jesus Christ has proved himself able to drive them [the gods], not only from their temples, but from the hearts of their worshipers (Augustine. City of God. pp135-6)

This perspective of Augustine captures, I think, the glory of the Kingdom of Christ. His Kingdom is not confined to the lands of the 'free' but can unmask and dethrone the powers of the nations even without altering the boundaries of the empire!