The Defender of Grace
Prosper's first securely datable act is a letter he wrote to Augustine around 428 or 429. According to the Catholic Encyclopedia, a certain Hilary had written to Augustine about difficulties raised against his doctrine at Marseilles and its neighbourhood; Prosper, described as a man distinguished for morals, eloquence, and zeal, wrote as well. Though he had never met Augustine, he had corresponded with him, and he made the defense of Augustinian teaching on grace and free will the work of his life.
He composed a short treatise on grace and free will addressed as a letter to Rufinus, and a great dogmatic poem of over a thousand hexameter lines, the De Ingratis (Adversus ingratos), directed against those whom he regarded as the enemies of grace. After Augustine's death, Prosper produced abridgments and compilations of his works, including a collection of epigrams and maxims drawn from Augustine's writings, helping to transmit and popularize Augustinian theology.
Rome and the Papal Chancery
In 431 Prosper and a friend traveled to Rome to invoke the aid of Pope Celestine I in the controversy over grace; the pope responded with the letter known by its opening words 'Apostolici Verba,' addressed to the bishops of Gaul.
About the year 440 Prosper was summoned by Pope Leo the Great and attached to the papal service in a secretarial or notarial capacity. According to the testimony of Gennadius, he was said to have drawn up the letters written by Leo against the heresiarch Eutyches, linking him to the doctrinal labors of the Roman see in the era of the Council of Chalcedon.
Writings and Legacy
Prosper's literary output secured his lasting influence. His Epitoma chronicon, a world chronicle, was carried down to the year 455 and was updated in several recensions; it remains an important historical source for the fifth century. He is also credited with the treatise De vocatione omnium gentium ('On the Calling of All Nations'), composed around 450, and with De gratia Dei et libero arbitrio.
Through these works, and through his epigrams and compilations from Augustine, Prosper became a principal channel by which Augustinian thought on grace and predestination passed into the later Western tradition.
Relics & Shrines
The available sources do not record the location of relics or a shrine associated with Prosper of Aquitaine. He is reported by tradition to have died at Rome around 455.
Miracles & Traditions
Historically Documented: The sources record no miracles attributed to Prosper; his renown rests on his theological writings and his service in the controversies over grace.
Traditional Accounts: By tradition Prosper served as amanuensis or secretary to Pope Leo the Great, and is said to have drawn up Leo's letters against Eutyches, though the sources transmit this on the authority of Gennadius rather than as documented fact.