According to Bart Ehrman on "jesus interrupted" Papias was an unreliable source. maybe he was a good reporter of second or third hand information. His writings helped the early church fathers to "guess" who wrote Matthew and Mark.
Interesting to note that Mark did not write what he saw but rather what he heard Peter say about Jesus life. Seems that Peter didnt remember much of Jesus life because although he spent three years with Jesus he only remembered 16 chapters...
Here is some info from the new world encyclopedia
Writings
Papias' Explanation of the Sayings of the Lord seems to have been not only an interpretation of Jesus' words, but also a collection of his sayings, gleaned not only from the Gospels but also from first-hand and second-hand accounts from the apostles, disciples, and other "elders" (presbyters) whom Papias encountered. Papias himself describes how he gathered his information, in an account preserved by Eusebius of Caesaria:
…I formerly learned with care from the presbyters (elders) and have carefully stored (what I learned) in memory, giving assurance of its truth… And also if any follower of the presbyters happened to come, I would inquire for the sayings of the presbyters, what Andrew said, or what Peter said, or what Philip or what Thomas or James or whatJohn or Matthew or any other of the Lord's disciples, and for the things which other of the Lord's disciples, and for the things which Aristion and the Presbyter John, the disciples of the Lord, were saying. For I considered that I should not get so much advantage from matter in books as from the voice which yet lives and remains.
Mark and his Gospel: Papias describes Mark as writing from memory what he heard from Peter.
Papias thus reports that his information came largely from an unwritten, oral tradition of the presbyters, apparently meaning elders. However, a great deal of debate resulted from Papias' use of the term, by which he seems to mean sometimes first-generation apostles and disciples of Jesus, and sometimes other elders who were hearers of the apostles. His work thus represents a kind of "sayings" or logia tradition passed down from Jesusthrough the apostles and disciples. Contemporary scholars such as Helmut Koester consider him to be the earliest surviving written witness of this tradition (Koester, 1990 pp. 32f) Papias also seems to have collected stories regarding the earliest history of the church after Jesus' death.
Papias' preserved writings also provide an early testimony concerning the origins of the Gospels. He explained that Mark, whom he characterizes as the companion and Greek translator of Saint Peter, wrote the earliest Gospel after having listened to Peter relate accounts of Jesus' life and teachings during their travels together. However, Papias admits that Mark, while writing nothing "fictitious," did not record the events of Jesus' ministry in their exact order, and that he wrote from memory of Peter's teachings, not from notes. Matthew, says Papias, wrote in Hebrew, offering a different, though still sincere, interpretation of Jesus' life and teachings. The fragment preserved by Eusebius relative to this is as follows:
Mark, having become the interpreter of Peter, wrote down accurately whatsoever he remembered. It was not, however, in exact order that he related the sayings or deeds of Christ. For he neither heard the Lord nor accompanied him. But afterward, as I said, he accompanied Peter… Wherefore Mark made no mistake in thus writing some things as he remembered them. For of one thing he took especial care: Not to omit anything he had heard, and not to put anything fictitious into the statements… Matthew put together the oracles [of the Lord] in the Hebrew language, and each one interpreted them as best he could.
It is debated, however, whether the Gospels of Matthew and Mark to which Papias refers were the same as the ones we know today. In Matthew's case, for example, Papias seems to refer to a "sayings" Gospel rather than a narrative one—referring only to the "oracles" of Jesus rather than both "sayings and deeds," as in Mark's case. Also, in the case of both Gospels, scholars have noted significant differences among the earliest manuscripts, all of which postdate Papias. Thus it is impossible to know with certainty what version of either Gospel he himself knew.
Papias also related a number of traditions regarding Jesus' teaching concerning the coming Kingdom of God, characterizing it as a literal reign on earth in which fruit, grain, and animal life would be marvelously productive, and humans would enjoy delicious foods. Eusebius called these and other teachings of Papias "strange parables and teachings of the savior, and some other more mythical accounts." Regarding the latter we know that Papias related an account of Judas Iscariot immediately before his death, in which he describes Judas in gruesome detail as grotesquely swollen, putrid-smelling, and possessing huge genitalia. Papias also reported a story about a certain disciple named Justus Barsabas, who drank snake venom but suffered no harm. He also related a tale via a daughter of Philip the Evangelist concerning the resurrection of a corpse (Hist. Eccl. 3.39).
Eusebius further states that Papias "reproduces a story about a woman falsely accused before the Lord of many sins." Although Eusebius did not elaborate, biblical scholar J. B. Lightfoot identified this with the Pericope Adulterae—the story of the woman taken in adultery. Since the story does not appear in the earliest manuscripts of the Gospel of John, many scholars believe that the Pericope Adulterae must have been a later addition, and Papias seems like a likely candidate as the written source of the story. Critic Michael W. Holmes has pointed out that it is not certain "that Papias knew the story in precisely this form, inasmuch as it now appears that at least two independent stories about Jesus and a sinful woman circulated among Christians in the first two centuries of the church, so that the traditional form found in many New Testament manuscripts may well represent a conflation of two independent shorter, earlier versions of the incident" (Lightfoot, 1989, 304).
