The synoptic gospels are Matthew, Mark and Luke, so called because of their similarity in content and structure. Their treatment of the life of Jesus is so remarkably similar that scholars have identified a common textual source, Q, said to have been used in their composition.
Mark has 661 verses, Matthew has 1068 verses, and Luke 1149. Matthew and Luke share 235 verses with identical language said to come from the Q document. Matthew and Luke also draw content from Mark. 500 verses, and 350 verses respectively.
One explanation for this similarity is that each writer was inspired by the same spirit, this is a slightly naive position that doesn’t really deal with the convincing evidence on hand.
The four compelling arguments for interdependence are:
1. Jesus words and deeds are recorded in near exact wording – for example, the feeding of the 4,000 in Mark 8:1-10 and Matthew 15:32-39, the healing in the synagogue in Mark 1:21-28 and Luke 4:31-37, and the healing of the leper in Mark 1:40-45, Matthew 8:2-4, Luke 5:12-16. If you were to argue that spiritual inspiration accounts for this similarity them you cast doubt on John’s gospel which is not similar when telling many stories that appear in the other gospels.
2. There is significant agreement in the ordering of events in the synoptics – though there is some disagreement this can largely be attributed to authorial intention, and a stylistic decision to group similar events together.
3. There is further agreement in parenthetical content – it is highly unlikely that the writers would choose to include the same verbal sides, or inserted editorial comments, if they were not drawing from a common source.
4. Luke’s preface – Luke begins his account by acknowledging the existence of other accounts with the implicit notion that he drew from them in forming his own.
I have no problems with a common literary source, or a recording of things Jesus said while he was alive and ministering, being used to formulate the later accounts of his ministry. I don’t think anybody believes (though I might be wrong) that Matthew, Mark and Luke followed Jesus around with a quill, recording his every word – especially because Luke wasn’t on the scene, and the only evidence Mark was is speculative guess work that he wrote a couple of self deprecating coded references to his own folly in the gospel.
We’ve established that the gospels were written with some reference to each other, and that Matthew and Luke share large portions with Mark. The question of which gospel came first has vexed scholars since the first century (in my opinion pretty unnecessarily).
Scholarship originally believed there were two documents floating around in the background – Q, and some sort of gospel ur-text (original text). After some deliberation and a dash of Ockham’s razor, it was decided that the Ur-text looked almost exactly like Mark, so it must in fact be Mark. Scholars have pretty much settled on the idea that Mark came first, for a number of reasons (not all are created equal):
1. Length – Mark is shorter than the others. It is almost totally present in Matthew and Luke, but they are not totally present in Mark, and although Mark is shorter than Matthew and Luke he is more long winded when it comes to shared accounts. Mark also misses a bunch of pretty important parts of Jesus ministry – like his birth and resurrection. A guy named Styler said “given Mark, it is easy to see why Matthew was written; given Matthew, it is hard to see why Mark was needed.”
2. Grammar and archaic language – Mark uses bad Greek (often fixed up in Matthew and Luke), and includes Aramaic expressions not included in the other two. Why would Mark add Aramaic back into his source? He also uses redundancies in his reporting that the others cut out. Much like sub-editors.
3. Mark writes tricky (or socially awkward) stuff without explanation, the other two explain it or leave it out.
4. Matthew and Luke rarely (if ever) use the same language as each other when they are not also agreeing with Mark.
5. The three use a similar ordering of events (though occasionally varying). Those variances are never the same in Matthew and Luke – when Matthew and Luke choose to disagree with the ordering of evensts from Mark they go in different directions.
6. The argument from redaction – most of the differences in the accounts of Matthew and Luke fit with their theological purposes – Matthew writes a lot about fulfillment, and refers to Jesus as the “son of David” three times more than either Mark or Luke. Mark uses the “historical present” significantly more than Matthew or Luke (151 times verses 78 and 9). The historical present (bringing life to the past by referring to it as present) was not a popular literary device in the first century, and Luke shows significant aversion to it.
7. Theological development – I don’t really buy this one so much, because I think it makes a tenuous jump on the base of terminology that also fits in with the author’s implied reader. Mark uses the Greek word kυριoς (lord) significantly less than the other two – who often modify “rabbi” or “teacher” to “Lord” which was one of the more popular terms for Jesus in the early church. It was also, incidentally, a title for Caesar.
In order for Markan priority, and Q, to be plausible Matthew and Luke must not have known of each other’s work, If Matthew and Luke were aware of each other Q is completely unnecessary. Most of the reasons above for Markan priority are diluted in this case, and Matthean priotiy becomes more attractive.
There are a bunch of problems with the idea that Matthew and Luke were unaware of each other. They’re outlined (as is everything previously written here) in this useful article. It concludes by suggesting that resolving this issue helps to date the gospels, which is useful for exegesis. The author of the article, Daniel Wallace, adopts the two source hypothesis and concludes that each gospel was probably written before 62 AD – which has significant implications because this predates the destruction of Jerusalem and the temple in 66AD. Flying in the face of those liberal postmodern scholars who think that everything supernatural and prophetic was the result of redaction by an oppressed Jew after Nero. Here’s another article outlining different synoptic theories.
How the “synoptic problem” influences exegesis
An awareness of the similarities and differences between gospel accounts means that when we come across differences in accounts we should ask “why has this writer chosen to put this in (or leave this out)? What does this add to their message? Who is this story aimed at? Being aware that different authors included different accounts deliberately helps us to properly assess the significance of these changes. Having a position on priority gives a base for comparison between the accounts.
What I think (or why the two source hypothesis doesn’t bother me)
As somebody who wrote press releases for a living, and who was always happy to see those releases picked up verbatim by the media, though with their own story angles added, I have no problem with the idea that the gospel writers were writing from a common source and fleshing out the accounts based on their intended audience. That doesn’t make their message any less true, it just makes their messages more targeted to particular groups of people. I have no problem with that. It makes sense. People who think this presents problems regarding the truth or authenticity of the gospel accounts have rocks in their heads.