Researchers discover previously unpublished sermons by Saint Augustine hidden in Poland.

The diocesan library of Pelplin, in the Pomerania region of northern Poland, unknowingly held a true treasure. Located next to the imposing Gothic cathedral where Cistercians have prayed for centuries, this repository of knowledge preserved a medieval manuscript whose importance has only recently come to light.

In 2024, Paul Alexander Nebauer, an independent researcher specializing in the medieval history of the former Cistercian monastery of Bad Doberan, Germany, contacted Christian Tornau, professor of classical philology (Latin studies) at the University of Würzburg, with a mission: he had located a medieval codex containing several sermons attributed to Saint Augustine and needed help identifying and translating them.

Tornau, considered one of Germany’s leading experts on the works of Saint Augustine of Hippo and late antiquity Christian literature, accepted the challenge. To an untrained observer, the manuscript might appear to be little more than a collection of aged, yellowed pages with the smell of an old document. However, the exhaustive philological research conducted by Tornau, along with Clemens Weidmann, a researcher at the Corpus Scriptorum Ecclesiasticorum Latinorum (Corpus of Latin Ecclesiastical Writings, or CSEL, for its Latin acronym) in Vienna, Austria, and a team of young scholars, ultimately revealed a discovery of immense importance.

The manuscript was copied at the Doberan monastery during the 12th century and may have been transcribed from an older codex originating from Amelungsborn, a historic Cistercian monastery located in the present-day German state of Lower Saxony. Of the four sermons analyzed, two were already known to specialists: one recognized as authentically Augustinian and the other classified as pseudo-Augustinian. The other two, however, could not be immediately identified.

“We transcribed the new texts and began analyzing them with a view to a future edition. We were fascinated, of course, by the idea of ​​having found new sermons by St. Augustine, but we soon became skeptical because, in some places, the sermons did not appear to have been written by Augustine,” Tornau explained to ACI Prensa, the Spanish-language sister service of EWTN News.

Without being carried away by initial excitement, the researchers wanted to subject the discovery to the highest academic standards before validating it. “Our final verdict that they are authentic is the result of continuous philological work over almost two years,” noted the German scholar.

Part of this work was carried out during a summer school organized by CSEL in Vienna in 2025, with the participation of doctoral students and early-career researchers specializing in early Christian literature. After a meticulous analysis of the texts and their manuscript transmission, the team concluded that there were no serious objections to attributing them to St. Augustine.

According to the researcher, although several centuries of textual transmission separate the era of Saint Augustine (5th century) from the surviving manuscript, the document offers a surprisingly reliable version. “Several centuries separate Augustine from this 12th-century scribe, so it’s easy to imagine that errors occurred during transmission. However, we have a very good text and, with some critical corrections, we can largely reconstruct what Saint Augustine said,” he explained.

Among the most compelling arguments are the dating of the sermons to late antiquity—between the 5th and 7th centuries—as well as the description of liturgical practices that, in Tornau’s words, “would have been unimaginable in the Middle Ages.” Furthermore, according to the researcher, “the context is North African, as is evident in the final prayer of the first sermon, which is attested only in late antiquity Africa.”

Experts also confirmed that the author possessed a deep understanding of Augustinian thought, without, however, simply reproducing it mechanically. “The preacher is familiar with the thought and works of Saint Augustine, but he doesn’t simply copy them—which could be a sign of inauthenticity,” he explained. He further added that “the sermons contain nothing that could not have been said by Augustine, whether from a linguistic, exegetical, or theological point of view.”

After comparing expressions, arguments, and textual characteristics with the existing body of Augustinian works, the researchers reached a firm conclusion. “Since the preacher is indistinguishable from Saint Augustine, we consider it methodologically correct to accept the authorship of Saint Augustine instead of inventing an anonymous ‘disciple’ or ‘follower’,” explained Tornau.