ABSTRACT
Sometime around 400 CE, as Augustine’s campaign to unify the African Christian church was gathering momentum, an excerpt of a letter from Petilian, the Donatist Bishop of Cirta, to his own clergy was brought to Augustine’s attention. Even before he obtained a complete and authenticated copy of Petilian’s letter, Augustine composed a response. His unsolicited intervention in Petilian’s correspondence is preserved among the libri as the first book of the Contra litteras Petiliani.1 Augustine addressed the treatise to his most beloved brothers (dilectissimi fratres), a category which we should understand to include both his Caecilianist co-religionists and those Donatist laymen who might be persuaded to embrace the catholica veritas.
