The City of God · Chapter
Book XV: The Progress of the Two Cities explained
Augustine explains the growth and progress of the earthly and heavenly cities from Cain and Abel to the deluge, using the allegory of Abraham's two sons to illustrate the distinction between the children of the flesh and the children of pro
What happens
Augustine explains the growth and progress of the earthly and heavenly cities from Cain and Abel to the deluge, using the allegory of Abraham's two sons to illustrate the distinction between the children of the flesh and the children of promise, and contrasting the fratricide of Cain with that of Romulus.
Themes in this chapter
The Two Cities
Augustine distinguishes the earthly city (Cain, Romulus) from the heavenly city (Abel, Isaac), tracing their origins and progress through biblical history.
Sin, Grace, and Redemption
The fall of humanity through Adam's sin, the condemnation of the mass, and the grace that redeems some to become citizens of the heavenly city.
Peace, Justice, and the Order of Love
The contrast between the earthly city's lust for dominion (fratricide) and the heavenly city's peace through grace and charity.
Characters to notice
- Augustine
Author and narrator, explaining the origin and progress of the two cities.
- Cain
Firstborn son of Adam, founder of the earthly city, and a fratricide who killed his brother Abel.
- Abel
Second son of Adam, a sojourner on earth and citizen of the heavenly city, killed by his brother Cain.
- Abraham
Father of two sons, Ishmael and Isaac, who allegorically represent the two covenants and the two cities.
- Romulus
Founder of Rome, who committed fratricide by killing his brother Remus, mirroring Cain's crime.
- Paul
Apostle whose writings (e.g., to the Galatians) are cited to interpret the allegory of Abraham's sons and the two covenants.
- Sarah
Free wife of Abraham, mother of Isaac, representing the heavenly city and the covenant of promise.
- Isaac
Son of Abraham and Sarah, born according to the promise, a type of the children of the free woman.
Key passages
“Thus the founder of the earthly city was a fratricide. Overcome with envy, he slew his own brother, a citizen of the eternal city, and a sojourner on earth.”
Cain, the first builder of a city, killed his brother Abel out of envy, showing the pattern of the earthly city.
Augustine draws a parallel between Cain's murder of Abel and Romulus's murder of Remus.
“For the city of the saints is above, although here below it begets citizens, in whom it sojourns till the time of its reign arrives, when it shall gather together all in the day of the resurrection; and then shall the promised kingdom be given to them, in which they shall reign with their Prince, the King of the ages, time without end.”
The heavenly city exists in heaven but produces citizens on earth who live as pilgrims until the resurrection, when they will reign with Christ forever.
Augustine explains the pilgrim nature of the city of God on earth.
“Which things are an allegory: for these are the two covenants; the one from the mount Sinai, which gendereth to bondage, which is Hagar.”
Paul interprets Abraham's two sons as an allegory of the two covenants: Hagar represents the old covenant of bondage, Sarah the new covenant of freedom.
Augustine uses Paul's allegorical reading to connect the two cities to the two covenants.
