J. Arnold: Heresiography as Pastoral Care and Reform: Benoit d'Alignan's Tractatus Fidei and Its Long Afterlife

Benoit d'Alignan, bishop of Marseille, wrote his monumental Tractatus fidei contra diversos errores between 1240 and 1261, attempting to address within it 'all' error against the Christian faith, from antique philosophy to the heresies of his own time (Waldensianism, Catharism) and 'erring' faiths with which he had direct contact (Islam, Judaism, Eastern Orthodox Christianity). He built his text primarily through what we would now call plagiarism, copying and adapting huge amounts of other scholarship.

His work is unusual in its breadth, but also in its ambition as a tool against 'all error', for use by all who defended the faith. This lecture will argue that it is best understood fundamentally as a pastoral
work; and this makes particularly interesting the fact that many of its manuscript copies were produced in the late fourteenth and early fifteenth century, in the context of Schism, reform, and a new set of heresies.

John Arnold bio
John Arnold studied at the University of York, gaining a BA in History, and a D.Phil. in Medieval Studies. He worked at the University of East Anglia, then moved to Birkbeck, University of London, in 2001, until his election to the professorship of medieval history at Cambridge in 2016. He has been lead editor of the journal Cultural and Social History, is on the editorial board of the journal Past & Present, is co-editor of the publication series 'Heresy and Inquisition in the Middle Ages' (York Medieval Press), and in 2019 took over as General editor of the series 'Cambridge Studies in Medieval Life and Thought' (Cambridge University Press). More:https://www.hist.cam.ac.uk/people/professor-john-h-arnold