St. Augustine, bishop of Hippo, stands as one of the towering figures of all history and, in particular, of the Christian church. Roman Catholics and Protestants alike acknowledge the stature of this Latin father. Among Augustine’s many enduring works, none rises to loftier heights than City of God. As his longest work, City of God is panoramic in its sweep of history.
Augustine’s work, often referred to by its Latin name De Civitate Dei, traces world history along two tracks: that of God’s people, the believers who belong to the heavenly city, and that of the people who belong to the worldly city. City of God divides into four main parts, which in turn make up twenty-two “books”:
Books 1-10. A defense of Christianity
Books 11-14. Origin of the two cities
Books 15-18. History of the two cities
Books 19-22. Destiny of the two cities
Augustine begins the first part by discussing the fall of Rome—the great city has lost her glory—and ends it with a discussion of the glory of Christ.
The immediate occasion for De Civitate Dei was Alaric’s sack of Rome on August 24, 410. For some time before that, however, neo-paganism had been on the rise. An aristocrat named Volusianus, of the town of Tubursicubure not far from Hippo, represented those Romans who longed for the days when Rome flourished under its deities. Such traditionalists saw Christianity as a foreign import which had weakened the empire.
In attacking Christianity, traditionalists presented two chief arguments: (1) Christianity taught renunciation of the world and turned away from service to the state. Christian virtues like turning the other cheek supposedly led to social and military weakness and (2) Rome’s destiny was bound up with its gods, who were now displeased with the empire that had spurned them.
Moved by the request of a Roman official in North Africa, “my dear Marcellinus,” Augustine set to answering the challenge of Volusianus. Marcellinus wanted Augustine to refute the pagan charges that Christianity was responsible for Rome’s fall. He also hoped for the conversion of Volusianus (who would later become a deathbed convert). This setting offered a natural introduction to a discussion of the two cities. On the one hand, pagans such as Volusianus were attributing Rome’s decline to the Christian faith. On the other hand, Christians such as Augustine’s friend Marcellinus wished to defend their faith and counter the pagans.
In writing City of God, Augustine sought to demonstrate that the events of 410 were but a glimpse of all history. Against the first argument from traditionalists, Augustine countered that many pagans had promoted the same virtues as Christianity, virtues such as forgiveness. Besides, Christianity did not forbid believers to serve the state and bear arms for it. In connection with this, Augustine presents the idea of “just wars.” “For we see that foreign iniquity has cooperated much in extending the empire by making foreigners so unjust that they became people with whom just wars might be carried on, with the result that the empire increased.” 
In writing City of God, Augustine sought to demonstrate that the events of 410 were but a glimpse of all history.
As for the second argument, Rome fell, Augustine contended, not because of its bulging Christian population, but because of its continued devotion to weak pagan gods. In its devotion to its own ineffective deities, Rome is a type of all people outside the city of God. The city of this world has given itself to that which is less than the true God. This basically is what constitutes worldliness and sin.
Toward the end of the first book of City of God, Augustine argues that Roman devotion to the old religion was frequently merely a smoke screen for devotion to self-indulgence: “Why in your calamities do you complain of Christianity, unless because you desire to enjoy your luxurious license unrestrained and to lead an abandoned and profligate life without the interruption of any uneasiness or disaster? . . .”  Rather than give one’s allegiance to gods and goddesses such as Felicity or Victory, Augustine asks, why not worship the true God? “For He sends, not Victory, who is no person, but His angel, and causes whom He pleases to conquer.” 
The first part of City of God covered ten books. Each of the other three parts covers four books. While the first part contrasted Rome with Christianity, the next three parts deal with the entire world as it stands in contrast to Christianity.
The second part of City of God (Books 11-14) traces the origin of the two cities—going back to the fall of the angels and of man—and follows a chiastic structure; with the two outer books corresponding to each other, as do the two inner books.
In the third main division of City of God (Books 15-18) Augustine outlines all of history. Drawing from the Bible, he traces the development of history up to his own time and then projects beyond that to the end of the world. Again, he uses a chiastic structure. He relates the history of the two cities from Adam to Noah (15), then focuses on the city of God—from Abraham to David (16) and from David to Christ (17)—before returning to his discussion of both cities (18).
The fourth and last part of City of God (Books 19-22) discusses eschatological matters. Once again, as in parts two and three, Augustine has the two outer books correspond with each other and the two inner books with each other, with the loftier subject matter standing at the beginning and end of the section. Augustine discusses the value of peace for both cities (19), the final judgment (20) and justice of eternal punishment (21), and the eternal joys of heaven (22).
The concept of two cities is scriptural. Two psalms use the term “city of God.” Psalm 46 says, “There is a river whose streams make glad the city of God . . .” (Ps 46: 4-5). Here the psalmist uses a river as a metaphor for the blessings of God, which flow out to his people. Psalm 87 also mentions the city of God: “. . . Glorious things are said of you, O city of God” (Ps 87: 1-3).
In the New Testament, the writer to the Hebrews also alludes to this topic: “For here we do not have an enduring city, but we are looking for the city that is to come” (Heb 13:14). The Apostle Paul refers to believers living in tents, as opposed to more permanent structures, here on earth: “Now we know that if the earthly tent we live in is destroyed, we have a building from God, an eternal house in heaven . . .” (2 Cor 5:1).
It was Augustine who both popularized the linear (versus cyclical) view of history and dealt with it in such convincing fashion that it has left its mark on Western historians ever since. What the Bible describes are one-time historical events. For ancient writers like Augustine, the accuracy of the scriptural record, including miracles, was accepted fact. To him the biblical account was inspired by God and accurate. Consequently, it had an advantage over every other history.
It was Augustine who both popularized the linear (versus cyclical) view of history and dealt with it in such convincing fashion that it has left its mark on Western historians ever since.
Present-day Christian apologists and historians also emphasize the Bible’s reliability, including its account of the resurrection of Jesus Christ, upon which Christian faith rests. Christian Apologist John Warwick Montgomery argues, “God did enter human life—in the person of Jesus the Christ—and did reveal to men the nature and significance of history and human life, and did bring men into contact with eternal values. ‘God was in Christ,’ says the Christian proclamation, ‘reconciling the world unto himself.’”  Montgomery sets this view of history against the approaches of Kant, Hegel, Marx, and Toynbee: “They all reflect what has often been called the ‘human predicament’—the lack of absolute historical perspective on the part of finite man,”  a lack for which the divinely revealed record of the Bible offers the solution.
Augustine had been able to take biblical information and apply it in broad strokes to all of history. Although at times he showed himself to be a man with feet of clay, overall, he created such an impressive work that it may have intimidated generations of Christian historians. After all, Augustine covered history up to the end. What more is there to talk about? A number of themes suggest themselves: the worldwide spread of Christianity, the encounter with Islam, the rise of atheistic communism—all issues that have arisen since Augustine’s time.
Contemporary apologists, theologians, and historians have treated these and similar topics. As yet, however, nothing has spurred an undertaking on the scale of City of God. The challenge is there. Even if such a work appears, Augustine’s De Civitate Dei will remain a magnificent guide to understanding the past and anticipating the future. In Christ.