The Nag Hammadi library (also known as the "Chenoboskion Manuscripts", or as the "Gnostic Gospels") is a collection of Gnostic texts discovered near the Upper Egyptian town of Nag Hammadi in 1945. Twelve leather-bound papyrus codices buried in a sealed jar were found by a local farmer named Muhammed al-Samman. The writings in these codices comprised fifty-two mostly Gnostic treatises, but they also include three works belonging to the Corpus Hermeticum and a partial translation/alteration of Plato's Republic. In his introduction to The Nag Hammadi Library in English, James Robinson suggests that these codices may have belonged to a nearby Pachomian monastery, and were buried after Saint Athanasius condemned the use of non-canonical books in his Festal Letter of 367 A.D. The discovery of these texts significantly influenced modern scholarship into early Christianity and Gnosticism.
The contents of the codices were written in the Coptic language. The best-known of these works is probably the Gospel of Thomas, of which the Nag Hammadi codices contain the only complete text. After the discovery, scholars recognized that fragments of these sayings attributed to Jesus appeared in manuscripts discovered at Oxyrhynchus in 1898 (P. Oxy. 1), and matching quotations were recognized in other early Christian sources. Subsequently, a 1st or 2nd century date of composition circa 80 AD or earlier has been proposed for the lost Greek originals of the Gospel of Thomas. The buried manuscripts date from the 3rd and 4th centuries.