Didache is a word meaning the “ of the Apostles.” It was written in the second century. The Metropolitan of Nicomedia, Philotheus Bruennios, discovered it in 1883. The author of this text is likely to have been of Hebraic origins. Many Fathers of the Church such as Clement of Alexandria, Eusebius, and Athanasius used quotations from this book. Serapion, Bishop of Thmuis, quoted it in his liturgy.

In Egypt, the Oxhyrhynchus papyri contain the first two chapters of this book, and a Coptic of the text is preserved in the Library. The unique complete manuscript was copied in the 11th century. The Didache starts with a discussion of how one should live one’s life, then describes liturgical practices, prayers, and the Eucharist, and concludes with pastoral instructions.