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Prochoros Kydones' Translation of Augustine's "On True Religion"


On True Religion is one of Augustine's most influential works. Written in 390, just before Augustine became a presbyter in the church of Hippo, it offers an introduction to Christian Theology from a variety of perspectives, philosophical, Biblical, and spiritual. It contains seminal treatments of a number of themes which Augustine was going to develop in later works, for example in The City of God and in The Trinity.

One of the most fascinating episodes in the history of the transmission of On True Religion is the 14th century, a time of lively exchange between the Latin West and the Greek East. In the course of this exchange works of Classical and Ecclesiastical authors in Latin were translated into Greek and had considerable impact on Byzantine intellectual life.

On True Religion was one of these works. There exists in the Vatican Library a single manuscript of a translation of part of the work by a Byzantine monk, Prochoros Kydones, brother of the more famous scholar and diplomat Demetrios Kydones. It is part of a substantial portfolio of translations and copies of texts which some way or other ended up in the Pope's library some time in the second half of the 14th century and forms indeed one of the oldest collections of what is now the Vatican Library.

Project aims

The aim of this project is to study Prochoros Kydones' translation, to produce an edition and a translation of it in comparison with the Latin original, and to explore the fascinating background of Prochoros Kydones' translation project.

For example, there are traces that lead to the Papal Court at Avignon and to the mysterious figure of Francesco Petrarca, who shared an interest in Augustine and in Neoplatonism with his Greek tutor Barlaam of Seminara, who regularly exchanged letters with other Byzantine intellectuals. Petrarch owned a rare copy of Augustine's On True Religion (still extant in the Bibliothèque nationale in Paris) and may well have played a role in communicating the importance of the work to its Byzantine translator.


Parts of the project have been funded by the British Academy, Cardiff University and the Exzellenzcluster "Religion and Politics" Münster.


Activities linked to the dissemination of research outputs included the delivery of a paper at the Sixth International Patristic Conference at Queens University, Belfast, July 2005, and a colloquium on the reception of On True Religion at the Exzellenzcluster "Religion and Politics", University of Münster, in May 2010.


Lössl, J., "Augustine in Byzantium," in: Journal of Ecclesiastical History 51 (2000) 267-295

Lössl, J., Augustinus. De vera religione / Die wahre Religion (Paderborn: Schöningh, 2007)

Lössl, J., "Palamite Soteriology in Augustinian Dress? Observations on Prochoros Kydones' Writings and Translations of Some Works of Augustine," in: D.V. Twomey & D. Krausmüller (eds), Salvation According to the Fathers of the Church (Dublin: Four Courts Press) 153-164


Prof Josef Lössl


Tel.: ++44-29-208-75499