In the early centuries of Christianity, there were over 200 Christian gospels in circulation, all of them containing wildly varied stories and theologies1. As the Church became organized there was much worry that no-one truly knew what Jesus had said or done, so they ratified just four Gospels: They picked the number four because "there were four winds, four points of the compass, four corners of the temple", mirroring the arguments of Irenaeus in the 2nd century - "just as the gospel of Christ has been spread by the four winds of heaven over the four corners of the earth, so there must be four and only four Gospels"2. The four canonical gospels comprise of synoptic gospels (Matthew, Mark and Luke) plus John. None are eye-witness accounts of Jesus' life and they are all written in Greek, not in the native tongues of anyone who met and followed Jesus. Many of the stories in the Gospels are copied from Greek god-man legends, especially those of Dionysus and Osiris. Although we now know them by the names of Matthew, Mark, Luke and John, they are all originally anonymous3.
Mark is the earliest gospel, composed between 60 and 80CE, by a Roman convert who was unfamiliar with Jewish customs and who had not met Jesus. The oldest versions of Mark all ended at Mark 16:8 with the words "according to Mark", and an unknown author at some point added Mark 16:9-20.
Matthew and Luke both used Mark as their source material (92% and 54% copied, respectively), except they corrected many of his blunders about Jewish life and added additional material from a second source document that historians call "Q"4. Matthew was written after 70CE and before 100CE. The first two chapters of Matthew were not present in the first versions and were added later by an unknown author. Luke was written after 93CE and uses Josephus's Jewish Antiquities. It claims to have been written by a travelling partner of Paul but the text contains too many mistakes with regards to Paul, and was written too late, for that to be true. Matthew and Luke copied such a large portion of their texts that it is clear neither were eye-witnesses, or friends-of-eyewitnesses, of Jesus.
John was written last. Our earliest fragment of it dates from 125CE. It has Jesus speak using completely different language, sentence structure and style to the other gospels. It contradicts the others on almost every point of history. Most people assume that John was writing figuratively writer and not attempting to record history, but was instead set out to write interesting and meaningful stories about Jesus, who was by then, famous. John is considered the least trustworthy of all the gospels.
“Irenaeus goes on to argue that these four gospels and no others belong in a Christian canon. He is talking about our four Gospels, so they must have existed and even been collected by his time, in the late second century C.E. Suddenly they are known, in the very time the emerging Catholic church was trying to co-opt the success of the Marcionite church by adopting its New Testament canon, padding it out with, among other things, three more gospels than Marcion had and a doctored version of the one he did have, Luke.”
"Incredible Shrinking Son of Man: How Reliable Is the Gospel Tradition?" by Robert M. Price (2003)5
“The four Gospels... are all anonymous, written in the third person about Jesus and his companions. None of them contains a first-person narrative ("One day, when Jesus and I went into Capernaum..."), or claims to be written by an eyewitness or companion of an eyewitness. Why then do we call them Matthew, Mark, Luke and John? Because sometime in the second century, when proto-orthodox Christians recognized the need for apostolic authorities, they attributed these books to apostles (Matthew and John) and close companions of apostles (Mark, the secretary of Peter; and Luke, the travelling companion of Paul). Most scholars today have abandoned these identifications, and recognize that the books were written by otherwise unknown but relatively well-educated Greek-speaking (and writing) Christians during the second half of the first century.”
“Justin Martyr, writing around 150-60 CE, quotes verses from the Gospels, but does not indicate what the Gospels were named. For Justin, these books are simply known, collectively, as the 'Memoires of the Apostles.' It was about a century after the Gospels had been originally put in circulation that they were definitively named Matthew, Mark, Luke, and John. This comes, for the first time, in the writings of the church father and heresiologist Irenaeus, around 180-85 CE.”
Ehrman kindly points out that the gospels were not forgeries - they were anonymous, and it was a case of false attribution8 by Christians later on that was the cause of the misdirection which lasted many hundreds of years.
Mark was written between 60 and 80CE. Matthew copies 92% of Mark, and Luke (written after 93CE) copies 54% of it. So Matthew and Luke share much of the exact same wording because they both used the same text. But they also share precise wording in many portions that do not occur in Mark. So historians conclude that a second common source was used. They call it "Q" after the French word for "source".
All of the gospels went through periods of alteration, editing and manipulation. Of the thousands of fragments we have from the very earliest times possible, no two copies of the same text are actually exactly the same. In some gospels, entire chapters were added by later editors.
The search for the earliest material is tantamount to working out which portions of the text of the gospels are most trustworthy. But the search is a difficult one, and there are many assumptions and mistakes even by those much closer to the time - who were themselves trying to work out "what had happened". It is clear that even by 120CE there was no consistent record of Jesus' life.
“For some decades there had been rumours floating around that two important figures of the early church had written accounts of Jesus's teachings and activities. We find these rumours floating already in the writings of the church father Papias, around 120-30 CE, nearly half a century before Irenaeus. Papias claimed, on the basis of good authority, that the disciple Matthew had written down the sayings of Jesus in the Hebrew language and that others had provided translations of them, presumably into Greek. He also said that Peter's companion Mark had rearranged the preaching of Peter about Jesus into sensible order and created a book out of it. [But] everything he says about these two books contradicts what we know about (our) Matthew and Mark: Matthew is not a collection of Jesus's sayings [and] was not written in Hebrew, but in Greek; and it was not written - as Papias supposes - independently of Mark, but was based on our Gospel of Mark. As for Mark, there is nothing about our Mark that would make you think it was Peter's version of the story [...] instead it derives from the oral traditions about Jesus that 'Mark' had heard after they had been in circulation for some decades.”
The theory was that the Gospels were based on eye-witness testimony of Jesus' life.
“This anonymous gospel was the first to be written, around 80CE, by an unknown Roman convert to Christianity. The Gospel of Mark has undergone many changes and there are several ancient versions, none of which are exactly the same. The oldest versions of Mark all end at Mark 16:810, many with the words "according to Mark" - the document was someone's record of what someone called Mark had told them11. 16:9-20 was a later addition by another unknown author12.
The author of Mark was not an eyewitnesses of Jesus, and wasn't friends with any of the disciples nor any other witnesses who could have easily corrected many of his mistakes. The evidence is that (1) the author uses a lot of existing stories (both Hebrew and Greek) and wrote them into the text with Jesus as the centre of the story, instead of the original characters. (2) He didn't speak Aramaic (Jesus' language) and wrote in Greek, not Hebrew, even having Jesus quote a Greek mistranslation of the Old Testament13. (3) Some details such as what Jesus said in his personal prayers is made-up. (4) He included multiple copies of the same story (but often with different details - evidence that he was using passed-on stories that had diverged over time). This often results in internal contradictions and inconsistencies. (5) The unfamiliarity with Jewish ways of life. There was no-one to correct his blunders such as misquoting the 10 commandments, attributing God's words to Moses, and having Jews buy things on the Sabbath.
Many of the Gospel of Mark's mistakes were edited and corrections were attempted by Matthew and Luke when they made their own copies of Mark (together there are only about 30 verses that they didn't copy).”
“The Gospel of Matthew is a later copy of the Gospel of Mark14, using 92% of its text. It is anonymous3 and it wasn't until about 150CE that the author "Matthew" was assigned15. It was written after the fall of the Jewish temple in 70CE, in Syria, and almost definitely written before 100CE. It went through several versions, probably edited by different authors, until it reached its final form by the 3rd century. The first two chapters, the birth of Jesus and the genealogy, were not found in the early versions.
Matthew not written by an eye-witness of Jesus. We know this because it is a copy of Mark. No eye witness of such an important person would have needed, or wanted, to simply copy someone-else's memories about him. It is written in Greek and not in the native tongues of anyone who met and followed Jesus, and it was written too late to reasonably be the memóires of an eye-witness.
Matthew specifically set out to correct many mistakes in Mark's gospel, especially regarding comments on Jewish customs and practices. Matthew was also written in order to debate some theological points, and had Jesus comment on those arguments, even though the disagreements hadn't arisen until after the supposed time of Jesus. Therefore, the gospel gives away the fact that it more of a theological argument than an historical account.”
“The Gospel of Luke is the third book in the New Testament. It copies over half of Mark14 and also uses Josephus's Jewish Antiquities as a reference and so must have been written after 93CE, probably after anyone who had known Paul (or Jesus) was already dead. The place of origin of Luke's writing is unknown. Luke existed in a single-book form in 140CE when it was used by Marcion, and this early version was anonymous. There are some major edits in later versions, especially involving the insertion of the virgin-birth in Luke 2:33 and Luke 2:4816. Later versions were "padded out" with extra inserted text, and had enough text added at the end that it had become known as the Acts of the Apostles and was included independently as the fifth book in the New Testament17.
It might be that the character of Luke was based on an old Roman pagan story about the healing God, Lykos, from Greek culture, and hence why the text was given the name Luke. Luke uses Mark, and 'Q', as sources of information. Out of Mark, 54% is quoted in Luke, and there are a hundred or so versus that, along with Matthew, he took from the source known as 'Q'. It is surprising that a first-hand eyewitness of Jesus would need to copy so much of other people's text about Jesus. Luke contradicts the rest of the Bible on quite a few points of theology and gets many elements of Jesus' life simply wrong (for example, the Roman-decreed census that never actually happened). For these reasons Luke is best not considered trustworthy.”
“The Gospel of John was written around 120CE18,19,20. The text is anonymous7 and definitely not written by the apostle called John21 nor by any eyewitness21, although the early Christian church promoted this as such22. We do know that the author was from Ephesus (in Asia Minor). The oldest surviving fragment of John is from 125CE. The earliest versions did not contain the final chapter, which describes Jesus Christ appearing to his disciples after rising from the dead.
It is significantly different from the other gospels in style and theology23. The Gospel of John is an interpretation of events in Jesus life24 that the author had heard about, but, with no real parables25 and instead, some plays on words and figurative, symbolic and abstract speech24. The other three gospels have Jesus speak tersely, in witty sayings, but 'John quotes lengthy speeches in fluent Greek' and is clearly not replicating the words of Jesus himself26. Miracles and events that were only ever seen by John are suspect (no-one else wrote about them!)24. It is best to consider the Gospel of John to be imaginative fiction or spiritual encouragement, but not strictly factual nor historical23.”