On August 24 of the year 410, the Visigoths under Alaric entered Rome, and they plundered the city for several days. Within weeks, word of the catastrophe had been conveyed throughout the Roman Empire, even to a small North African town called Hippo, which had been blessed with a bishop named Aurelius Augustine. The greatest theologian of the early church, Augustine was faced not only with the unthinkable reality of Rome’s fall, but also with the unique challenge that those in Rome blamed Christians for the empire’s demise. They claimed that Christianity had weakened the political will of Rome and distracted the empire’s leaders from their task. Christians, they claimed, had angered the pagan gods the Romans had once worshiped, and this was the inevitable result. Rome had fallen.
Augustine gave his answer to these challenges in the most magnificent work of political theology ever undertaken by a Christian theologian. In The City of God, Augustine said that there are two cities, each with a corresponding love and a separate destiny. The first of these cities, the city of God, is marked by a love of God and of divine things which orders all else. The other city, the city of man, is marked by the love of human beings — not so much the love of human beings for one another, but the love of human beings for themselves. Augustine argued that Rome fell because it was an unbelieving city, made up of people who acted as if the most important reality was the city of man, and who rejected the ultimacy of the city of God. Having lost sight of the heavenly city, they lost the security of the earthly city as well.
Augustine’s notion of the two cities is very important. If there is a danger in our age, it is that our society, as well, would confuse the city of God for the city of man, exchanging the love that we should properly find in the heavenly city for the truncated, false love of the city of man. History is replete with examples of humanitarian philosophies, rooted only in the city of man, which turn out to be something other than humanitarian. Defining themselves against a horizon no larger than humanity itself, human beings have ended up building not Utopia but Dachau, Treblinka, and the killing fields of Pol Pot.
There is an equal danger for Christians. If the liberal, humanistic temptation is to confuse the city of man for the city of God, it just might be that the conservative temptation is to ignore the city of man altogether. Both are forms of sin. Both are an abdication of Christian responsibility. As Christians, we understand that our earthly calling is only a foretaste of what is to come. It is a test of our discipleship, and it is a trial through which we are now passing. Yet just as we are to love the city of God, we are also to love those who are in the city of man. We are not to love both cities, but for the sake of the Creator, we are to love those whom He has created — the citizens of the kingdom of man.
Scripture tells us how to maintain a proper perspective here. In Matthew 22:35–40, a lawyer came to Jesus and asked him, “Teacher what is the greatest commandment in the Law?” Jesus answered, “You shall love the Lord your God with all your heart, and with all your soul, and with all your mind. This is the great and foremost commandment. The second is like it: You shall love your neighbor as yourself.” A proper understanding of how we are to relate to the city of man even as we find our ultimate citizenship in the city of God is to be found within this very text, and in these two commands — love of God and love of neighbor.
Love of God and love of neighbor are tied inseparably together. Love of God leads us to love of our neighbors, and a proper love of our neighbors is one that is rooted in genuine love of God. If that is so, then our motivation for political engagement and cultural concern is first of all love of God, and second, love of neighbor.
Loving our neighbors for the sake of our love for God is the most profound political philosophy one could possibly find, and it is rooted here in the authoritative revelation of Jesus Christ. As Christians, we do not engage in political action because we believe the conceit that politics is all-important, but neither do we believe the lie that politics is inconsequential. We are concerned for the culture not because we believe that our greatest fulfillment is to be found in the artifacts and achievements of culture, but precisely because we believe that love of neighbor compels us to be concerned for the common weal. We believe that love of neighbor compels us to be concerned for liberty. We believe that love of neighbor compels us to be concerned for freedom in every corner of the world. Our concern as Christians should be to see our neighbors saved from an immediate peril that we may have the opportunity to proclaim to them the Gospel so that they might be saved from an ultimate, eternal peril. Like Augustine, it is love of neighbor — rooted finally in love for God — that compels us to want and hope and pray for the good of our society.