I crafted this quote heavy essay two years ago for a message exchange with a Christian guy named David on Dawson Bethrick’s blog Incinerating Presuppositionalism regarding Papias and Christian origins.
David: "you should wonder why the early church leadership chose to attribute Marcan authorship when they knew he was writing down Peter's words. Why not put Peter at the wheel, if you know that this will guarantee the story gets in the stack?"
David’s query begs the question in several ways. By asserting that I should be concerned about (presumably) the Jesus myth case because of Christian apologetical assertions that canonical Mark was authored by the legendary secretary John Markus to Simon Peter the Apostle and that putting Peter at the wheel gets the story into the stack is circular reasoning because that is to assume the gospel stories are historical. The historicity of the Gospel story is, however, the issue at question.
It is Petitio principii to think there was “leadership” in early Christianity because doing so assumes a “big bang” origin of Christianity with a legendary founder, Jesus of Nazareth. In fact, Christianity was always a schizophrenic diversity of cultic expression characterized by many sects each with a writhing, squirming, wad of competitive would be prophets and apostles. Christianity was never a single organization prior to the darkness of total Catholic control. Asserting there was 2-nd century consensus begs the question.
To suggest Irenaeus’ agenda of establishing his four gospels as authoritative was contested is to ignore the Sitz im Leben of late second century Catholicism and to assume that the other types of Christianity then extant would be in any way influenced by what they considered gross error. Would the Gnostics or Jewish-Christian sectarians have been influenced by Irenaeus? Of course not. Who was there in the 2-nd century to say what was scripture and what was not? The religious landscape of 2-nd century Rome was a free-for-all. There were Holy Ghost’s, Prophets-Of-The-Real-Gods, Apostles-O-Christ-du jure on every street corner. Vast numbers of phony preachers and cult leaders competed for followers and their loot, and there was no end to the fools and loons who willingly followed. The much later Church Councils and Synods of the fourth century were 150 to 200 years yet to come relative to Irenaeus. However, his writings were influential with third and fourth century Catholics in establishing preferred dogma. The later churchmen then accepted Irenaeus’ recommendations (an reliance on Papias) because his gospels told the story in a manner compliant with their desire to create an authoritative institution issuing command catechism. Irenaeus’ claim regarding authorship of Mark stem from Papias. However, the zany notion that the canonical Gospel of Mark was authored by the legendary secretary John Markus to Simon Peter the Apostle as per Papias cannot be substantiated from what historical data we have.
Since the four canonical gospels do not show up in the literary record prior to Irenaeus naming them in "Against Heresies,"
"After their departure (death of Peter & Paul), Mark, the disciple and interpreter of Peter, did also hand down to us in writing what had been preached by Peter." - (Against Heresies 3:1:1)
we can reasonably accept a strong prior probability that were canonical Mark and Matthew in circulation prior to Irenaeus, that Quadratus of Athens, Aristides, Marcion, Polycarp, Justin Martyr and other early 2-nd century apologists would have used them. But the early 2-nd century Christian churchmen do not cite or quote canonical Mark and Matthew.
It is likely that Irenaeus ascribed authorship of what we think of as the canonical Gospel According to Mark to Presbyter John’s Mark based on data from Papias about a quite different document. Paul Tobin’s case thoroughly refutes evangelical assertions that canonical Mark was the document thought to be known to Papias. He explains:
"The first explicit references to the supposed authors of the gospels were from Irenaeus (c130-200). Thus we see him making references to the gospels according to Mark, Matthew, Luke and John in Against Heresies (c 180)
Against Heresies 3:10:5 Wherefore also Mark, the interpreter and follower of Peter, does thus commence his Gospel narrative: "The beginning of the Gospel of Jesus Christ, the Son of God..." [Mark 1:1]"
The earliest attempt to give the names of the authors of some of the gospels came just before the middle of the second century. This is the witness of an early Christian named Papias, bishop of Heirapolis. He wrote a now lost work entitled The Five Books of Interpretations of the Oracles of the Lord. The actual time of his writing is unknown, and is now available only in fragments quoted by later Christians. Most scholars place it around 130 CE, but it could well be as late as 150 CE. In any case, this is what Papias wrote - as quoted in Eusebius's (c275-339) History of the Church:(Book III, Chpt.39, Art.1)
Quoted in History of the Church 3:39:15
And the presbyter said this: Mark the interpreter of Peter, wrote down exactly, but not in order, what he remembered of the acts and sayings of the Lord, for he neither heard the Lord himself nor accompanied him, but, as I said, Peter later on. Peter adapted his teachings to the needs [of his hearers], but made no attempt to provide a connected narrative of things related to our Lord. So Mark made no mistake in setting down some things as he remembered them, for he took care not to omit anything he heard nor to include anything false. As for Matthew, he made a collection in Hebrew of the sayings and each translated them as best they could.
His source for this information is one Presbyter John. Who is this mysterious person whom Papias quoted? We do not know. We do know that he was not one of the apostles, as earlier in the same work Papias wrote this:
Quoted in History of the Church 3:39:3-4
And whenever anyone came who had been a follower of the presbyters, I inquired into the words of the presbyters, what Andrew or Peter had said, or Philip or Thomas or James or John or Matthew, or any other disciple of the Lord, and what Aristion and the presbyter John, disciples of the Lord, were still saying.
Note that the presbyter John is not included in the list of the apostles and is not to be confused with the apostle John who was mentioned earlier in the sentence and in the past tense. There is a further point we should note about the witness of Papias. According to Eusebius (History of the Church 3:39:13-14), Papias was a man "of very limited understanding" who "misunderstood apostolic accounts." In other words he must have been, even for his age, quite credulous. We do not foresee such a person counter-checking the reliability of the information given to him by the presbyter. He probably just accepted what was told to him verbatim.
[Robert_B: Presbyter John’s story is that his Mark took notes from speeches delivered by Apostle Peter. Our canonical Mark is a narrative story, not a collection of logia sayings.]
Whatever the case may be as to the reliability of this tradition (which we will consider below), Papias' testimony tells us that the name Mark was attached to the gospel around 130-150 CE. Prior to this the document we call the Gospel According to Mark circulated anonymously. It is unlikely that our Gospel According to Mark was the same document Papias referred to. Richard Bauckham in "Jesus and the Eyewitnesses: The Gospels as Eyewitness Testimony" (Eerdmans 2006) admits that modern scholars have regarded Papias testimony on Mark as "historically worthless." (Bauckham, Jesus and the Eyewitnesses: p203) – Paul Tobin’s web article Was Papias a Reliable Witness?
[Robert_B: We know about Papias from Irenaeus through Eusebius. Both Irenaeus and Eusebius are known to have exaggerated and must be approached skeptically
It is quite certain that the Christian landscape of the 2-nd century was saturated with itinerant, vagabond, preachers-teachers-prophets-apostles who traveled about swindling credulous Christian believers. Even Paul warned about such in 2 Cor 11:4. The Didache warns against such itinerant apostles..
Let every apostle who comes to you be received as the Lord. But he shall not remain more than one day; or two days, if there's a need. But if he remains three days, he is a false prophet.
[Robert_B: We cannot, therefore, rule out that presbyter John was not a swindling con-man who targeted Papias as a mark.
Richard Packham in "Critique of John Warwick Montgomery's Arguments for the Legal Evidence for Christianity" notes regarding Papias that: "The testimony of Papias is the earliest authority for the authorship of the Apostles, but it is scarcely "solid." We do not even have Papias' direct testimony, since his writings are lost. Our information about Papias' testimony comes only by way of Eusebius, who wrote in the fourth century, and who portrays Papias as being somewhat gullible. The "John" of whom Papias was a student was more likely John Presbyter than John the Evangelist (or John the Apostle, if they can be proven identical). In short, the "solid" evidence is not as solid as Montgomery would like us to believe."
Supernatural Religion: An Inquiry Into the Reality of Divine Revelation (full view available on Google Books) Walter Richard Cassels presents a thoroughly convincing case that canonical Mark is not the same document as that spoken of by Papias. The argument starts on page 276 and runs through 286.
Cassels concluded that: "It is not necessary for us to account for the manner in which the work referred to by the Presbyter John disappeared, and the present Gospel according to Mark became substituted for it. The merely negative evidence that our actual Gospel is not the work described by Papias is sufficient for our purpose. Any one acquainted with the thoroughly uncritical character of the Fathers, and with the literary history of the early Christian Church, will readily conceive the facility with which this can have been accomplished. The great mass of intelligent critics are agreed that our Synoptic Gospels have assumed their present form only after repeated modifications by various editors of earlier evangelical works. These changes have not been effected without traces being left by which the various materials may be separated and distinguished ; but the more primitive Gospels have entirely disappeared, naturally supplanted by the later and amplified versions. The critic, however, who distinguishes between the earlier and later matter is not bound to perform the now impossible feat of producing the originals, or accounting in any but a general way for the disappearance of the primitive Gospel.
Tischendorf asks : "How then has neither Eusebius nor any other theologian of Christian antiquity thought that the expressions of Papias were in contradiction with the two Gospels (Mt. And Mk.)?"
The absolute credulity with which those theologians accepted any fiction, however childish, which had a pious tendency, and the frivolous character of the only criticism in which they indulged, render their questioning application of the tradition of Papias to our Gospels anything but singular, and it is only surprising to find their silent acquiescence elevated into an argument. We have already, in the course of these pages, seen something of the singularly credulous and uncritical character of the Fathers, and we cannot afford space to give instances of the absurdities with which their writings abound. No fable could be too gross, no invention too transparent, for their unsuspicious acceptance, if it assumed a pious form or tended to edification. No period in the history of the world ever produced so many spurious works as the first two or three centuries of our era. The name of every Apostle, or Christian teacher, not excepting that of the great Master himself, was freely attached to every description of religious forgery. False gospels, epistles, acts, martyrologies, were unscrupulously circulated, and such pious falsification was not even intended, or regarded, as a crime, but perpetrated for the sake of edification. It was only slowly and after some centuries that many of these works, once, as we have seen, regarded with pious veneration, were excluded from the canon; and that genuine works shared this fate, while spurious ones usurped their places, is one of the surest results of criticism The Fathers omitted to inquire critically when such investigation might have been of value, and mere tradition credulously accepted and transmitted is of no critical value. In an age when the multiplication of copies of any work was a slow process, and their dissemination a matter of difficulty and even danger, it is easy to understand with what facility the more complete and artistic Gospel could take the place of the original notes as the work of Mark." – Cassels, "Supernatural Religion" p.285-286
Charles B. Waite in his definitive - "History of the Christian Religion: To the Year Two Hundred" wrote the following about Papias’ alleged witness to the Gospels According to Mark and Matthew.
*Such is this far famed testimony (Eusebius, Ecc. Hist. bk. 3, ch. 89.)
That portion relating to the Gospels of Mark and Matthew, may be stated as follows: Eusebius says, that Papias said, that John the presbyter said, in what manner certain writings of Mark and Matthew had been constructed. The value to be attached to any statements of Eusebius, will be considered hereafter. One important circumstance will be noted, in the evidence, as it stands: Notwithstanding this explanation of the apostolic origin of the books, it appears that Papias considered them, as evidence, inferior to oral tradition. That, too, a hundred years after the time, when, as is claimed, they were written. Again, it is contended by able critics, that the language here attributed to Papias, concerning the book written by Mark, cannot be applied to the gospel which bears his name. ' They insist that it must be referred to the Preaching of Peter, or some other document more ancient then the Gospel of Mark. So also of the logia, oracles or sayings of Christ, by Matthew, which were not the same as the Gospel of Matthew.* - "History of the Christian Religion: To the Year Two Hundred", By Charles Burlingame Waite (full view on Google books)
Papias’ credulity did not escape Eusebius who wrote of him that: 13. For he appears to have been of very limited understanding, as one can see from his discourses. Church History (Book III, Chpt.39, Art.13) That Papias would accept anything is evident by the surviving *fragment of Papias’ writing, preserved by Apollinarius of Laodicea, a fourth century Christian bishop, tells of the fate of Judas. It is important to read this passage in full:
Judas did not die by hanging, but lived on, having been cut down before choking. And this the Acts of the Apostles makes clear, that falling headlong his middle burst and his bowels poured forth. And Papias the disciple of John records this most clearly, saying thus in the fourth of the Exegeses of the Words of the Lord:
Judas walked about as an example of godlessness in this world, having been bloated so much in the flesh that he could not go through where a chariot goes easily, indeed not even his swollen head by itself. For the lids of his eyes, they say, were so puffed up that he could not see the light, and his own eyes could not be seen, not even by a physician with optics, such depth had they from the outer apparent surface. And his genitalia appeared more disgusting and greater than all formlessness, and he bore through them from his whole body flowing pus and worms, and to his shame these things alone were forced [out]. And after many tortures and torments, they say, when he had come to his end in his own place, from the place became deserted and uninhabited until now from the stench, but not even to this day can anyone go by that place unless they pinch their nostrils with their hands, so great did the outflow from his body spread out upon the earth. 
Anyone who reads this will immediately notice a few things. Firstly this is a harmonization of the contradictory readings from Matthew 27:3-5 and Acts 1:18-19. [b] Secondly the additional details, like his swollen head, sunken eyes, bloated genitalia, body flowing with pus, emanation of worms and terrible stench are typical motifs used by ancient authors to describe the deserved sufferings of evil men before their deaths. Josephus in Antiquities 17:6:5 described Herod the Great’s suffering before his death to include putrefied genitals, emanation of pus and worms and bad stench. Acts 12:23 describes the death of Herod’s grandson, Herod Agrippa I by stating that he was struck by an angel and was "eaten by worms." In other words the story about Judas suffering is an expected folkloric expansion of the brief accounts given in the Matthew and Acts. 
Obviously this fable recounted by Papias certainly did not come from eyewitness accounts. Yet he presented it quite matter-of-factly as though he was recounting real history!
There are further examples from available fragments of Papias’ writing of the basic unreliability of his writings. He was a teller of tall tales. In the fragment preserved by Philip of Side (c. 380 - c. 439), we hear of the daughters of Philip who would drink snake venom with no ill effects, of a woman resurrected and of those who were raised by Jesus surviving until the early second century!
The aforesaid Papias reported as having received it from the daughters of Philip that Barsabas who is Justus, tested by the unbelievers, drank the venom of a viper in the name of the Christ and was protected unharmed. He also reports other wonders and especially that about the mother of Manaemus, her resurrection from the dead. Concerning those resurrected by Christ from the dead, that they lived until Hadrian. 
We can now see why Eusebius noted that Papias writes of "strange parables" and "mythical tales." The latter’s credulousness is strong evidence that Papias was as Eusebius described him: someone of "limited understanding." As for his claim of diligent collection and remembering of the Jesus tradition from the elders, we have an example of this in Irenaeus. Irenaeus cited Papias as his source for this saying of Jesus about the millennium:
Against Heresies 5:33:3-4
As the elders who saw John, the disciple of the Lord, related that they had heard from him how the Lord used to teach in regard to these times, and say: The days will come, in which vines shall grow, each having ten thousand branches, and in each branch ten thousand twigs, and in each true twig ten thousand shoots, and in each one of the shoots ten thousand clusters, and on every one of the clusters ten thousand grapes, and every grape when pressed will give five and twenty metretes of wine…And these things are borne witness to in writing by Papias, the hearer of John, and a companion of Polycarp, in his fourth book; for there were five books compiled by him
The source of this saying attributed to Jesus is not from any extant Christian writing or oral tradition – but Jewish apocrypha! Compare the passage below from 2 Baruch, a late first century or early second century Jewish pseudepigraphical text.
2 Baruch 29:3-6
And it shall come to pass when all is accomplished that was to come to pass in those parts, that the Messiah shall then begin to be revealed. …The earth also shall yield its fruit ten thousandfold and on each (?) vine there shall be a thousand branches, and each branch shall produce a thousand clusters, and each cluster produce a thousand grapes, and each grape produce a cor of wine.
The above evidence tells us that Papias was not a careful historian but a credulous second century Christian who seemed eager to believe anything that confirms his faith in Jesus.* - Paul Tobin Was Papias a Reliable Witness?
In light of this stuff, the question of Peter-Mark-Papias is moot, for Papias was an unreliable witness. His testimony cannot be taken seriously by any honest exegetical investigator.