St. Ambrose (339-397) was the bishop of the Italian city of Milan. He was the outstanding leader, preacher, and author in the Western part of the Christian Church during the 4th century.
Born in the city of Trier (now in Germany), Ambrose was the son of one of the highest-ranking administrative officials of the Roman Empire, the praetorian prefect of Gaul. After the early death of his father, the family returned to Rome, where Ambrose received the liberal education appropriate to a high-ranking Roman who was to practice law and advance to high office in government service. In his late 20s he was employed in legal work at the imperial court, and at about 30 he was named governor of two provinces of northern Italy, in which capacity he resided at Milan. On the death of the bishop of Milan in 374, the people of the city demanded that Ambrose be made bishop, and he reluctantly yielded.
Ambrose's career as bishop had three important aspects: the quality of his thought as a Christian intellectual, his role in the final phase of the Arian controversy, and his impact upon the relations between Church and Empire.
The Western Church of the 4th century was notably lacking in men of high intellectual capacity, especially compared to such Eastern figures as Athanasius and Gregory of Nyssa. Ambrose went far in the task of integrating the Christian faith with a total world view acceptable to the sophisticated Latin minds of his age. This task was soon to be brought to brilliant fulfillment at the hands of Augustine, who as a young man was much influenced by hearing sermons of Ambrose and who was baptized by him at Easter, 387. Deeply imbued with Neoplatonic currents of thought and widely read in religious authors whose language was Greek, Ambrose succeeded in communicating elevated conceptions of God and of the Christian pursuit of virtue. In particular, he effectively employed allegorical interpretations of the Old Testament and thus freed his hearers from the necessity of entertaining conceptions of God and of God's relations with men which appeared unworthy when understood at a literal level. A number of Ambrose's most important writings, for example, the commentary on Luke's Gospel, were the product of revising and combining the notes taken by enthusiastic listeners to his sermons preached on scriptural texts. His work On the Duties of the Clergy is one of the first comprehensive treatments of Christian ethics.
The Arian controversy had raged in the Eastern Church since the early 320s. The central issue was whether belief in Christ as being fully God could be reconciled with strict monotheism. The orthodox answer to this question was affirmative, an answer that was finally ratified in the East at the Council of Constantinople in 381. In the same year a Western council met at the Italian city of Aquileia with Ambrose as president. His commanding leadership and vigilant political maneuvering assured the victory of the orthodox party, and nonorthodox bishops were removed from their sees by government action. In a series of dramatic incidents in 385-386, Ambrose, defying even an imperial threat on his life, successfully stood his ground in refusing to turn over a church in Milan for use by the nonorthodox party, one of whose powerful supporters was the Emperor's mother.
Ambrose held tenaciously to the central conviction that the Emperor, as a Christian, must execute his responsibilities as ruler in accord with the requirements of Christian faith. Threatening to excommunicate the Emperor, the bishop blocked a powerful movement in 384 toward erecting again the old pagan altar and statue of the goddess Victory in the Senate house at Rome. When, in 390, the emperor Theodosius, in a fit of rage over a bloody riot in the city of Thessalonica, had his soldiers massacre several thousand inhabitants, Ambrose brought the ruler to do public penance for his act of vengeance, again under threat of excommunication. The great bishop of Milan is therefore an important figure in the history of the relations between Church and State in the Western world. Ambrose served as bishop of Milan for 23 years until his death in 397.
The standard comprehensive work on Ambrose is F. Homes Dudden, The Life and Times of St. Ambrose (2 vols., 1935). A treatment of smaller scope but of great sensitivity is in Hans von Campenhausen, Men Who Shaped the Western Church (trans. 1964).