As noted elsewhere on this site, three gospels — those according to Matthew, Mark, and Luke — have many passages in common. Some passages are found in all three, while others are found only in two. There’s something of a convoluted interweave among them all, complicated by the apparently random nature of which parts are shared with which other gospels.
This interrelationship is known as “the synoptic problem.” The word “synoptic” refers to a synopsis or overview and comes from the Greek συνοπτικς (synoptikos) meaning “general or comprehensive view.” This is an allusion to the notion that the three gospels are all telling the same story.
That there are passages in common, among the three synoptic gospels, is not in question. What is in question is … pretty much everything else. Scholars have analyzed common passages from front to back, up and down, and in every direction possible, in an effort to understand how they all relate to one another; which of those common pieces came from where, and the nature of their inclusion in the documents they ended up in.
The scholars who first delved into the matter came up with a number of possible scenarios and connections. Over time, starting in the early 19th century, they plotted and cross-referenced passages in many directions. The scenarios they’ve distilled out of the synoptic problem fall into a number of categories and play out in various models.
The process of working this out, forced scholars to face some of the assumptions that Christians had long made about these gospels. Among them was the prevailing notion that the three synoptic gospels had been independently written by an apostle (Matthew) and companions or protégés of apostles (Mark and Luke). It was clear there had been borrowings of some kind, so independent authorship almost certainly had to be ruled out.
That, all by itself, was a remarkable conclusion that disrupted almost two millennia of Christian thinking about their sacred scripture.
As it happened, at nearly the same time as analysis of the synoptics was getting underway, the Great Awakening started, and in the United States at least, that movement led to the appearance of fundamentalist Christianity. Among the core beliefs of that form of the faith, is the assertion that scripture wasn’t written by human beings, but by the Almighty himself.
Under this model, similarities between gospels was to be expected; but the all-but-random shuffling of duplicated or triplicated passages, among these three gospels, appeared all but nonsensical. Why would God have chopped up the passages he’d used to dictate one book, include them in another but leave some them out of a third? And why would the three synoptics all have so much in common, while the fourth gospel (the one according to John) was unlike them in almost every way?
It was, and is, a lot to deal with. It was, and is, something some Christians refuse to accept, despite the obvious fact of the overlapping passages in the three synoptic gospels.
One aspect of the synoptic problem that got a lot of attention, are the portions of Matthew and Luke that both have in common, but which aren’t found in Mark. Some of these passages are found verbatim in both gospels, which strongly suggests a source each had in common.
Different scholars proposed different versions of what must have been in this now-missing document. Still, all were based on the material that was found in both Matthew and Luke, but not in Mark. Since most of the scholars doing this work were German, this missing source was known as Q, for the German word Quelle, which means “source.” This particular block of content could only have been a particular collection of Jesus’ teachings.
An early assumption had been that some other early Christian document was that source. However, an examination of extant writings didn’t align with the content this proposed source must have had. There were no extant Christian documents that were simply lists of Jesus’ teachings. There were references to, and even quotations of, documents of this type, such as Exposition of the Sayings of the Lord by the early Church Father Papias of Hierapolis (in Anatolia); but without anything of this kind in hand, assuming such a source must have existed appeared to be quite a stretch for most scholars. Many assumed they’d reached something of a dead end, given that there was no identifiable candidate to have been Q. Synoptic scholars were literally forced to engage in a good deal of speculation, which many were loath to do.
In 1945, an Egyptian farmer found a cache of codices (plural of “codex”) that had been buried in a very-old jar near the town of Nag Hammadi. This was a collection of previously-unknown books, virtually all of them related to Christianity. Among them was a codex now known as the Gospel of Thomas.
Remarkably, this book was something like what the proposed synoptic source, Q, must have been: A collection of Jesus’ teachings. The codex itself dated sometime in the 2nd century and was in the Coptic (Egyptian) language. The content of this document was compared with references to various works in other early Christian works. It appears to have been mentioned by Origen, among others, sometime in the early 3rd century, but other mentions date back to the 2nd century. And the document referred to by the Church Fathers was in Greek, so if this copy of the Gospel of Thomas is that same document, it must be a Coptic translation of it.
At first there was some excitement that Q had been “found” … but it was not to be. Something less than half of the teachings in the Gospel of Thomas are the same as, or similar to, teachings that had to have been in Q. And this newly-discovered gospel wasn’t necessarily old enough to have been Q. Still, this discovery confirmed that lists of Jesus’ teachings was a genre of document that early Christians had composed and copied. Which made it clear that Q might very well have existed, even if it didn’t survive to the present day.
Thus, Q is sometimes referred to as “the Lost Gospel.” It’s believed to have existed at one time but has since been lost to history as a distinct document, living on only as portions of Matthew and Luke.Since the text analyses that first demonstrated a relationship and commonalities among the synoptic gospels in the early 19th century, a number of different models have been proposed. The prevailing model also happens to be one of the oldest, and it’s known as the “two-source hypothesis.” This posits, very simply, that the authors of Matthew and Luke used both Mark and Q as their sources. It has the advantage of being simple, and can be diagrammed like this:
A related model accounts for the material that’s unique to each of the gospels of Matthew and Luke, called the “four-source hypothesis.” It posits that the authors of Matthew and Luke each had a unique, existing source, in addition to Mark and Q; it can be diagrammed this way:
Together, these two models are the prevailing view among scholars to explain the authorship of the synoptic gospels. Even so, there are other models, predicated on many other conceptions of how these documents are related.
All of this, however, is what scholarship says about the matter. If you ask the average rank-&-file Christian believer about the authorship of the gospels, he or she would probably say what Christian tradition has long said about them: Matthew was the work of the apostle Matthew, and Mark and Luke were written by companions of the apostles Peter and Paul, respectively. And quite aside from the synoptics, he or she would also say John had been written by the apostle John.
As I noted earlier, though, the texts themselves suggest otherwise. There are few scholars now who accept this, given the number of passages that are shared, verbatim, between two or three of the synoptics.
Still, there is a working theory as to how this might have happened, and that is that the three synoptics were composed independently by three different authors … but they’d all been exposed to the same body of oral tradition about Jesus, or perhaps different oral traditions that had all descended from eyewitnesses of Jesus’ ministry. This can’t be totally dismissed as a possibility, but the amount and length of exact passages shared among the three synoptics would seem to make this unlikely.
There are other hypotheses about the relationship of the synoptics. Some are in line with the old Christian tradition that the gospels had been composed in order as they’re presented in the Bible: Matthew first, then Mark, then Luke. Perhaps the best-known scenario of this kind was first proposed by St Augustine. Here, Matthew was written first; Mark was composed based on that; and both of those were used as sources by the author of Luke. It can be diagrammed as follows:
This theory has the advantage of simplicity: It doesn’t assume the existence of documents that aren’t known to exist. Still, this position has been reviewed, and while a few scholars adhere to it, not many do any more.
Other proposed scenarios involve other potential sources or intermediate documents that were either mentioned or quoted in classical times, but are no longer extant. Among them are the gospel of the “heretic” Marcion, and Papias’s Exposition (previously mentioned). Some of these had traction at some time or other, but they’ve mostly fallen by the wayside.
Fervent believers in the notion that the Christian Bible is the absolute, unassailable “word of God” have an easy out for all of this: What we see in the synoptics — and in the rest of the books of the Bible — are nothing more or less than what God himself wanted us to see in them. They were inspired or dictated by God, and they are what they are, based on his own design. There’s nothing about it that’s worth concerning oneself with, since they are what they are — period. Any other speculation is a waste of time that can only detract from the magnificent sanctity of God’s Holy Word. So it’s best to just put all of this business out of one’s head and be done with the matter.
It’s all well and good, I suppose, that scholars have been able to do these deep dives into the synoptic gospels and arrive at various conclusions about them. What’s important to understand is that there’s more to these gospels than meets the eye. While some Church Fathers (such as Origen, Augustine, and others) studied and wrote about them, for too long the vast majority of Christendom has simply taken Christian tradition at its word about them and ignored what’s been staring them in the face for centuries.
The bottom line is that Christianity’s literature has a lot to say not only about the faith, or even about the people who wrote that literature, but about the context in which those documents were written and the history that led up to them. It’s only within the last two centuries or so that any real attention has been paid to this, on a consistent basis.
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