The volume brings together two writings from the earliest Christianity: The Letter to Diognetus, composed at the end of the 2nd century in Alexandria as a promotional text for Christianity, is the response of a Christian teacher to the questions of his student Diognetus and addresses issues of the Christian faith: the concept of God, the distinction from paganism and Judaism, the love of Christians for one another, the situation of Christians in the world, the mystery of salvation, and the plan of salvation. The Epistle of Barnabas, written between 130 and 132 in Alexandria and attributed to an otherwise unknown Christian named Barnabas, is a treatise framed as a letter.