Researches on the borrowings of De Trinitate attributed to Didymus: A practice of cento?

Abstract To make progress in the much-debated question of the authorship of De Trinitate , we are continuing the investigation initiated by previous scholars into the similarities between this treatise and several other ancient authors. These parallels involve identical sequences of quotations, specific forms of biblical verses, similar commentaries on these quotations, or even the use of rare words. Our investigation, focused on analyzing the parallels between De Trinitate and Cyril of Alexandria’s Contra Julianum and the Dialogues on the Trinity , yields several results. Certain expressions that appear only in De Trinitate and in Cyril’s writings are frequent throughout Cyril’s work. Several of these parallels occur near confirmed borrowings of De Trinitate from other authors, some unquestionably earlier, such as Philo of Alexandria, Basil of Caesarea, or Epiphanius, and others that are more difficult to date, such as the Pseudo-Athanasian dialogues. However, none of these additional sources are shared with Cyril, which might have been expected if Cyril had borrowed from De Trinitate . Moreover, De Trinitate employs an expression that appears only in an excerpt from the Corpus Hermeticum quoted by Cyril. Within a chapter that presents numerous similarities with Cyril, there is also a specific expression from Proclus – something that is not unique, as Proclian vocabulary seems to be scattered throughout the work. The author of De Trinitate thus seems to reuse multiple sources in a variety of ways – quoting them verbatim, adapting, and combining them in the manner of centos. He may also do so with Cyril’s works, especially since the analysis of parallels makes it more likely that De Trinitate borrowed from Cyril than the reverse.