Fastidius

Almost everything known about Fastidius comes from a single paragraph. Gennadius of Massilia, writing his catalogue of Christian authors in the late fifth century, recorded: "Fastidius, a bishop of the Britons, wrote to a certain Fatalis one book on the Christian life, and another on preserving widowhood, sound in doctrine and worthy of God."

That is the whole biographical record. He was a bishop. He was British. He wrote two books. Gennadius places his notice among writers active in the first half of the fifth century, which puts him around 420, the generation that watched Roman troops leave Britain for good.

That makes him one of the earliest named Christian writers of the British Isles, from a church that existed well before Augustine of Canterbury landed in Kent in 597. Britain had bishops at the Council of Arles in 314. Fastidius belongs to that older, half-lost British church, and he is one of the very few voices from it we can put a name to.

A treatise called On the Christian Life survives, transmitted for centuries under the name of Augustine and later assigned to Fastidius on the strength of Gennadius's description. Most scholars now accept the attribution, though it is not certain.

The book is a letter to a Christian widow, and its subject is what the Christian life actually looks like from the outside. Its argument is uncomfortable and consistent: a Christian is known by conduct, not by profession. It presses hard on wealth, on the treatment of the poor and of dependents, on the difference between calling yourself a believer and living as one. "He is a Christian who does not merely say he is" runs the drift of it"but who is one in deed."

That emphasis, and the book's confidence about what a person can do if he chooses, place it near the movement Pelagius set off, and Pelagius was himself a Briton. Whether Fastidius was a Pelagian, a fellow traveler, or simply a moralist writing in the same idiom is disputed and probably unresolvable. What is not disputed is that Britain in the early fifth century was producing serious Christian writing about how to live, and exporting it.

Germanus of Auxerre crossed the channel in 429 to argue against Pelagian teaching in Britain, which tells you the argument was live there. Fastidius stands in the middle of it.

Sources: Gennadius of Massilia, De viris illustribus, 56; De vita christiana (Patrologia Latina 50); R. S. T. Haslehurst, The Works of Fastidius (1927); Prosper of Aquitaine, Chronicle.