Around 175 CE the early church leader Irenaeus expounded upon the information of Papias when he gave an account of the origin of each of the four Gospels that later became canon.
Matthew also issued a written Gospel among the Hebrews in their own dialect, while Peter and Paul were preaching at Rome, and laying the foundations of the Church.
It is important to note that we have one, and only one, source of information about the life of Jesus and that is the Christian Gospels.
The Gospels are the sole source of information about this figure; everything that we "know" about "him" depends on these sources.
Mark was said to have been a second-hand account which was out of order because events in the Gospel of Mark are the same as in the , but in a different order, and Mark does not contain the virgin birth story so it was seen as less valuable, thus, to resolve the contradiction between the order of events in Mark and Matthew, the idea that Mark was a second-hand account gained favor.
The attribution of Peter as the source of information for Mark comes from the fact that in order to be viewed as legitimate the Gospel had to be tied back to an apostle, and the Gospel of Mark seemed to come from Rome due to linguistic reasons, where the "apostle Peter" supposedly preached, as well as the fact that Peter was the most highly esteemed apostle, so Peter was proposed as Mark's source of information.
The traditional explanation for the origin of the Gospels has been that they were each written independently by people who were either disciples of Jesus or who received their information from disciples of Jesus.
There are several problems with what Papias and Irenaeus state, but first let's see what they are saying and why they are saying it.
Early Christian theologians believed the Gospel of Matthew to be the first Gospel that was written, and, by many accounts, the most important (of course there was disagreement among them, as there was on all doctrinal issues).
The belief in a literal "human" Jesus most likely emerged as eucharist rituals and theology developed around the concept of the "flesh" and "blood" of Christ and these concepts merged with allegorical narratives about the figure.
What is the basis for the claim that "Jesus never existed"?