Sources for the historicity of Jesus and actions attributed to him. Three of these (Matthew, Mark, and Luke) are known as the synoptic Gospels, from the Greek σύν (syn "together") and ὄψις (opsis "view"), given that they display a high degree of similarity in content, narrative arrangement, language and paragraph structure. The presentation in the fourth canonical gospel, i.e. John, differs from these three in that it has more of a thematic nature rather than a narrative format. Scholars generally agree that it is impossible to find any direct literary relationship between the synoptic gospels and the Gospel of John. The authors of the New Testament
New Testament Writings attributed to the apostles circulated among the earliest Christian communities and the Pauline epistles were circulating, perhaps in collected forms, by the end of the 1st century AD. One of the earliest attempts at solidifying a canon was made by Marcion, "circa" 140 AD, who accepted only a modified version of Luke (the Gospel of Marcion) and ten of Paul's letters, while rejecting the Old Testament entirely. His canon was increasingly rejected by other groups of Christians, notably the proto-orthodox Christians, as was his theology, Marcionism. Adolf Harnack in "Origin of the New Testament" (1914) observed that the church