A medieval artist's vision of the City of God

Born to a pagan father and a Christian mother, Augustine was in his youth a devotee of Manichean teachings. After a period as a teacher of rhetoric, he came under the influence of Ambrose of Milan and was drawn to Christianity. Augustine’s Confessions recount his protracted struggle with the Christian faith and dramatic conversion, in which his Christian mother Monica played a crucial role. After living for a short time in a semi-monastic community, he became a priest and soon thereafter bishop of Hippo. He continued in this office until his death.

Augustine's work as a theologian and architect of the western Christian tradition as definitively shaped by his tasks as a bishop. Among the most influential of his theological writings was his summary work, On Christian Doctrine. In controversy with the Donatists of North Africa, Augustine developed lastingly influential notions of catholicity in relation to the larger themes of his ecclesiology, an account of the relation of church and state, and a distinctive theology of ministry in relation to the administration of the sacraments. Augustine joined Jerome and others in controversy with Pelagius. In this context Augustine worked out durable conceptions of sin and grace. The fall of the city of Rome to barbarian invaders in 410 prompted him to write The City of God, a massive account of the work of God in human history. Augustine continued until his death to produce a prodigious volume of sermons, commentaries, and other works. Augustine was especially influential in the later development of ecclesiology, sacramental theology, and the understanding of the relation of sin to grace.