– Missing for more than 1,500 years, the earliest known Latin commentary on the Gospels has been rediscovered at the Cologne Cathedral Library and was published in English this week.

The biblical commentary, penned by the fourth century Italian bishop Fortunatianus of Aquileia, was originally rediscovered in 2012 by Dr. Lukas Dorfbauer, a researcher from the University of Salzburg.

Fortunatianus’s manuscript was widely known to have existed, although many scholars believed it had either been destroyed or permanently lost. St. Jerome had also pointed to the existence of this commentary in his work, Lives of Famous Men.

Dorfbauer found the 100-page document in an unmarked manuscript dating back to about 800 at the Cologne Cathedral Library, which had been digitized in 2002. While other scholars were aware of the document, the majority of its biblical content was overlooked.

But Dorfbauer’s curiosity persisted, and he further researched the manuscript to find that it was not just an anonymous document, but rather seemed to date back further than the ninth century.

He began to take notes on the document and cross-checked some of its contents with St. Jerome’s writings on Fortunatianus in the fourth century.

“I was able to compare the biblical quotations in the Cologne manuscript with our extensive databases,” said Dr. Hugh Houghton, the Deputy Director at the Institute for Textual Scholarship and Electronic Editing (ITSEE) at the University of Birmingham.

“Parallels with texts circulating in northern Italy in the middle of the 4th century offered a perfect fit with the context of Fortunatianus,” he said, according to The Conversation.

Digital technology was then enlisted from the University of Birmingham’s ITSEE department. Houghton, a specialist in the Latin New Testament, began to pull quotes from the rediscovered manuscript and compared it with other 4th century texts by using the university’s mega database.

He used a methodology for analyzing the text and found that the comparison “seemed to preserve the original form of Fortunatianus’s groundbreaking work.”

“Such a discovery is of considerable significance to our understanding of the development of Latin biblical interpretation, which went on to play such an important part in the development of Western thought and literature,” Houghton said.

The rediscovered Latin commentary from Fortunatianus now replaces the Vulgate as the earliest known Latin commentary of the Gospels. The Vulgate was translated from Hebrew and Aramaic into Latin by St. Jerome between 382-405, and was known as the earliest form of written Latin commentary of the Gospels.

The 160-chapter commentary mainly focuses on the Gospel of Matthew, but also includes brief references to the gospels of Mark, Luke and John.

Although this new document now predates the Vulgate, Houghton said, “It will still be some time before this work becomes as widely known as the famous writings of later Christian teachers such as Ambrose, Augustine and Jerome.”