patristic · treatise · c. 110–130 · Greek
Five books of an Exposition of the Sayings of the Lord, which no one has seen since the Middle Ages. What survives is quotation: Irenaeus, who calls him a hearer of John and a companion of Polycarp, and above all Eusebius, who copies out the preface and the paragraphs on Mark and Matthew while making clear he thinks little of the author's millenarianism. The fragments are the earliest external evidence for how the gospels were composed.