Three of the Gospels—Matthew, Mark, and Luke—are quite similar to each other when compared to the fourth Gospel, John. They tell the story of Jesus in similar ways, frequently including the same stories and sayings and often using the same words.
That’s why these three are known as the “synoptic” Gospels—because they offer a “shared view” of Jesus’ life (Greek, sun = “together” + opsis “seeing”).
They are so similar that scholars have long tried to figure out why. This is known as “the synoptic problem.”
In the last two centuries, there has been an enormous amount written about the subject, and we can’t hope to more than scratch the surface here. We will, however, look at some of the more popular solutions to the synoptic problem.
Is there a problem at all?
It’s tempting to ask whether there even is a problem to be solved. Relying on eyewitness evidence and oral tradition, couldn’t Matthew, Mark, and Luke have written independently of each other? Couldn’t they include the stories and sayings that they do simply because Jesus did and said those things?
This view is known as the Independence hypothesis, and it is the position that most people hold—at least before they start looking closely at the issue. Despite its appeal of simplicity, the Independence hypothesis has not won many advocates among scholars in recent years.
This is partly because of the Gospel of John. It is missing many of the familiar stories and sayings found in the other three, and it has a great deal of unique material. Furthermore, at the end of his Gospel, John writes: “There are also many other things which Jesus did; were every one of them to be written, I suppose that the world itself could not contain the books that would be written” (John 21:25).
That means we have to ask: Why did Matthew, Mark, and Luke choose the material they did? It’s clear they weren’t recording everything Jesus said and did. They could have picked different stories and sayings, like John. If they wrote independently of each other, why did they make so many of the same choices?
It is commonly estimated that 90 percent of the material found in Mark is also found in Matthew (B. F. Streeter, The Four Gospels, 160). Nine out of ten verses in Mark are paralleled in Matthew. That seems to be too much material in common to chalk up to random chance. It suggests a common source.
An oral Gospel?
What could that source be? One possibility is that it was an oral equivalent of a Gospel.
People had to rely on their memories to a much greater extent in the past, and it is not impossible that the early Church developed a standard way of recounting the ministry and passion of Jesus—a cycle of stories and sayings that were memorized in a definite order rather than just as a pool of traditions. If so, they had the oral equivalent of a Gospel, and the Synoptic Evangelists could have drawn on this for the material they have in common.
Most scholars have not favored this viewpoint. Memorizing such a Gospel would have been quite an achievement—particularly without a written text from which to work—and it is not clear that the early Christian community had enough people willing to perform the feat. Further, we have no record of people in the first century attempting this, and we have no record among the Church Fathers of the Synoptics being based on such a source.
A lost Gospel?
Most scholars think that the similarities among the Synoptics are due to a common written source. The question is: Do we still have this source?
Some have suggested that we don’t—that the common source behind the Synoptics was a now-lost “proto-Gospel” that each drew upon.
Luke tells us that, in his day, “many have undertaken to compile a narrative of the things which have been accomplished among us” (Luke 1:1). It is possible that the three Evangelists used one of these prior narratives in composing their own Gospels.
But we should be careful about claiming that there was a single, written source that explains the similarities among the Synoptics.
This view invokes a hypothetical source, and Occam’s razor indicates that we shouldn’t propose hypothetical sources beyond what is necessary to account for the data. Otherwise, the problem will become nightmarishly complex. (Indeed, one website devoted to the synoptic problem—hypotyposeis.com—listed 1,488 solutions! That number is made possible by freely proposing hypothetical sources for which we do not have clear evidence.)
Rather than proposing hypothetical lost documents, we should at least initially try to explain the material in the Synoptic Gospels by appealing to documents that we know existed: Matthew, Mark, and Luke.
Who’s on first?
It’s possible to explain the shared material in the Synoptics by proposing that one of them is the common source. In other words, one of the Evangelists wrote first and the other two borrowed from him.
You could explain the 90 percent of Mark that is paralleled in Matthew either by saying Mark wrote the first Gospel and Matthew borrowed from him or that Matthew wrote first and Mark did the borrowing.
You don’t need a hypothetical source to account of the material. You just need to identify which one was written first.
On this, there are two major views: that Matthew wrote first and that Mark did. Virtually no one in Church history has claimed that Luke wrote first.
The belief that Matthew wrote first is known as “Matthean priority,” and it was the most popular view throughout most of Church history. The alternative view, that Mark wrote first, is known as “Markan priority,” and it is the more popular view today.
The Augustinian hypothesis
For much of Church history, the standard theory of how the Gospels were composed is that Matthew wrote first; Mark then did an abbreviated version of Matthew, adding a small amount of material of his own; and lastly, Luke wrote.
This view takes its name from St. Augustine (354-430).
At the beginning of his Harmony of the Gospels, Augustine took the position that the Gospels were written in this order, though a statement that he made later in the work has led some to think that he may have revised his view or become less sure about the order.
The Griesbach hypothesis
Another view, known as the Griesbach hypothesis, agrees that Matthew wrote first, but it holds that Luke wrote second and that Mark wrote last, making his Gospel a combination and abridgement of the first two. (Mark is quite a bit shorter than either Matthew or Luke.)
The view is named after Johann Jakob Griesbach (1745-1812), the German scholar who proposed it.
This is the second most popular view among biblical scholars today. (We will discuss the most popular one shortly.) The best-known advocate of this theory in recent years was William Farmer (1921-2000).
The Farrer hypothesis
If you hold that Matthew wrote first, then the Augustinian and Griesbach hypotheses are the two obvious options. But what if you hold that Mark wrote first? Again, there are two options that don’t involve hypothetical documents.
The first is known as the Farrer hypothesis. According to it, Mark wrote first, then Matthew used and expanded on Mark, and finally Luke drew from and abridged the first two, while adding some new material from his own sources.
This view is named after the English scholar Austin Farrer (1904-1968), who proposed it. It is popular principally among British scholars.
The Wilke hypothesis
The other obvious view based on the idea that Mark wrote first is known as the Wilke hypothesis. According to this view, Mark wrote the initial Gospel; Luke wrote next, drawing partly on Mark and partly on his own sources; and then Matthew wrote last, drawing on both Mark and Luke.
This theory is named after the German scholar Christian Gottlob Wilke (1786-1854), who was a convert to the Catholic Church from Lutheranism.
The Wilke hypothesis has received a surprisingly small amount of attention in recent literature, with many authors gliding over it in a sentence or failing to mention it altogether. Despite that, it has been attracting renewed attention in the last few years from a number of new advocates. Among them was German scholar Martin Hengel (1926-2006), who proposed a version of it.
The two-source hypothesis
By far the most common theory today is the Two-Source hypothesis. According to this view, Mark wrote first, and then Matthew and Luke used him independently of each other.
This would account for why both Matthew and Luke have certain material in common with Mark, but it would not account for why they have certain material in common with each other.
There are around 235 verses in Matthew that are paralleled in Luke, and many scholars have proposed a common source for this material. They have dubbed this source “Q.” It is often claimed that this is short for the German word quelle, which means “source,” but this is not certain.
The view is known as the “Two-Source hypothesis” because it holds that Matthew and Luke used two major sources: Mark and Q.
Note that the idea of a Q source (which might have been written or oral) is needed only if you assume that Matthew and Luke wrote independently of each other. If you hold one of the views mentioned above, you don’t need to propose a Q source. For example, Luke could have drawn all of the so-called “Q material” directly from Matthew under the Augustinian, Griesbach, or Farrer hypotheses. Alternately, Matthew could have taken all of this material directly from Luke under the Wilke hypothesis.
The Two-Source hypothesis was proposed in 1838 by the German scholar Christian Hermann Weisse (1801-1861) and was elaborated by various others—most notably by the English scholar B. H. Streeter (1874-1937).
In 1911 and 1912, the Pontifical Biblical Commission issued a pair of decrees that insisted Catholic biblical scholars were to teach that Matthew wrote first, thus ruling out the Two-Source hypothesis.
These decrees were disciplinary and provisional, and they were ultimately superseded. The Two-Source view then became dominant among Catholic scholars.
This was acknowledged by Benedict XVI, before he became pope and while he was himself the head of the Pontifical Biblical Commission. In an address to the commission, he noted that the Two-Source theory is “accepted today by almost everyone” (Joseph Ratzinger, On the 100th Anniversary of the Pontifical Biblical Commission).
Upon coming into office, Pope Francis wrote a letter to an Italian newspaper indicating that he adheres to the idea that Mark wrote first: “I would say that we must face Jesus in the concrete roughness of his story, as above all told to us by the most ancient of the Gospels, the one according to Mark” (“Pope Francisco writes to La Repubblica: ‘An open dialogue with non-believers,’” La Repubblica, Sept. 11, 2013; online at repubblica.it).
Pope Francis did not indicate whether he also believes there to have been a Q source—and letters to newspapers do not count as acts of the papal magisterium—but this does indicate the degree of acceptance that Markan priority has achieved in Catholic circles.
How certain can we be?
By the mid-twentieth century, the Two-Source hypothesis had achieved such dominance that it was often presented as one of “the assured results of modern scholarship” (to use a common phrase).
But things began to change, with a notable number of scholars challenging it and with even its advocates scaling back claims on its behalf.
For example, Joseph Fitzmyer—an advocate of the Two-Source hypothesis—famously said: “The history of Synoptic research reveals that the problem is practically insoluble. As I see the matter, we cannot hope for a definitive and certain solution to it, since the data for its solution are scarcely adequate or available to us” (“The Priority of Mark and the ‘Q’ Source in Luke,” Jesus: Man’s Hope, 1:132).
Advocates of other views have often agreed that the best we can achieve is a probable solution. This is because the data we have is limited and often difficult to assess. Basically, it comes in two forms: external and internal.
External data consists of what we can learn about the Synoptic Gospels from outside sources, such as the Church Fathers. Internal data consists of what we can learn by comparing the Synoptic Gospels with each other. Both kinds can be difficult to assess.
The external data can be difficult because, although the Augustinian hypothesis remained the majority view for a long time, the Church Fathers do not all agree, particularly in the period before Augustine.
This can be seen by looking at what they have to say about Mark. According to Augustine, Mark was the second Gospel to be written, after Matthew and before Luke. He wrote: “Mark follows [Matthew] closely, and looks like his attendant and epitomizer” (Harmony of the Gospels I:2).
But Clement of Alexandria, Mark’s late-second-century successor as bishop of Alexandria, held Mark was written third—after Matthew and Luke, for he said the Gospels with the genealogies (Matthew and Luke) were written first (Eusebius, Church History 6:14:6-7). This would be in keeping with the Griesbach hypothesis.
The earliest statement we have comes from the early second-century historian Papias, who quotes a first-century figure known as “John the Presbyter” or “John the Elder” (Greek, presbuteros = “elder”). This figure was a disciple of Jesus. He is sometimes identified with John son of Zebedee, but a careful reading of Papias indicates that he was a separate individual (see Richard Bauckham, Jesus and the Eyewitnesses, chs. 2, 9, 16).
According to John the Presbyter, “Mark, having become the interpreter of Peter, wrote down accurately, though not in order, whatsoever he [Peter] remembered of the things said or done by Christ. For he [Mark] neither heard the Lord nor followed him, but afterward, as I said, he followed Peter, who adapted his teaching to the needs of his hearers, but with no intention of giving a connected account of the Lord's discourses, so that Mark committed no error while he thus wrote some things as he remembered them. For he was careful of one thing, not to omit any of the things which he had heard, and not to state any of them falsely” (Eusebius, Church History 3:39:15).
Since John the Presbyter is a first-century source and a witness of Jesus’ ministry, his testimony regarding Mark’s composition has great weight.
It was also held by many in the early Church (see Jerome, Lives of Illustrious Men 9 and 18) and by a number of modern scholars (including Richard Bauckham, Martin Hengel, and Benedict XVI) that John the Presbyter had a hand in writing at least some of the Johannine literature in the New Testament, especially 2 and 3 John, which are addressed as being from “the Presbyter/Elder” (2 John 1, 3 John 1; see Benedict XVI, Jesus of Nazareth 1:224-227 for his view of John the Presbyter’s role in the origin of the Johannine books).
If this is true, then his testimony regarding the origin of Mark’s Gospel would have even greater weight. It would represent the testimony of one of the other authors of the New Testament! (The same would be true if John the Presbyter were identified with John son of Zebedee.)
Either way, if Mark’s Gospel is based on his memory of things Peter preached, and if 90 percent of Mark is in Matthew, then it would seem that Mark wrote first and Matthew borrowed from him. It would seem hard to say that Mark is based on Peter’s preaching if 90 percent of it came from Matthew.
However, some advocates of the Griesbach hypothesis have proposed that Peter gave a series of lectures based on Matthew and Luke and that Mark had these lectures transcribed (so Dom Bernard Orchard, David Alan Black). In this way, Mark could be based on Peter’s preaching and still have so much of its material taken from Matthew.
Orchard and Black also propose that, although Luke was written before Mark, it was not published until afterward. They thus see the Griesbach hypothesis as representing the order of composition for the Gospels but the Augustinian sequence as representing their order of publication.
The idea that Mark had transcriptions made of Peter’s lectures, however, does not seem to correspond to what John the Presbyter says. He states that Mark “wrote down accurately, though not in order, whatsoever he remembered of the things said or done by Christ” based on Peter’s preaching, “with no intent of giving a connected account of the Lord’s discourses.” The stress is placed on Mark’s after-the-fact memory of Peter’s preaching, not on the transcription of a set of lectures.
If the external evidence can be difficult to assess, so can the internal evidence that scholars have gleaned by comparing Matthew, Mark, and Luke. The literature on the subject is vast, often brain-crushingly detailed, and frequently the arguments don’t prove what they claim to.
For example, one argument B. H. Streeter proposes for Mark being the first Gospel is that its literary quality is not as high as Matthew or Luke. This is true, and it is especially clear in the Greek text. The claim is that Mark reads like a first attempt at a Gospel and that Matthew and Luke then expanded on and polished the material, producing Gospels of higher literary quality.
Though this argument has weight, it is not conclusive. It is possible that Mark could have decided to do an abbreviated Gospel, and his retelling of the material revealed that he was not as accomplished an author.
Another argument is based on the fact that the Synoptics often present the same stories and sayings in a different order. Streeter argues that, when this happens, either Matthew tends to follow Mark’s order or Luke does. Matthew and Luke virtually never agree with each other against Mark’s sequence. This suggests to him that Matthew and Luke used Mark as a source but occasionally changed the sequence in which they presented material.
Unfortunately, this argument—like many—is reversible. As later scholars pointed out, the same phenomenon can be explained if Mark was compiling his material from Matthew and Luke. At any given point, it would have been natural for Mark to follow Matthew’s order or Luke’s order, but he couldn’t do both when they were different.
The difficulty in finding conclusive arguments—based on internal or external evidence—has convinced many scholars that we simply can’t have conclusive proof. The best we can hope for is a probable solution, and some scholars even think the matter is unknowable.
This leads to a final question.
How important is the synoptic problem?
The answer will depend on your perspective. For some scholars, the subject is crucially important. This is particularly the case for those engaged in “the search for the historical Jesus.” These scholars tend to think that the true Jesus—“the Jesus of history”—has been obscured by successive layers of tradition and dogma and so been transformed into “the Christ of faith.”
For them, finding the truth about Jesus involves peeling away and discarding the layers of tradition, and if you want to do that, then it matters very much which Gospel was first and whether lost sources like Q were being used. You need to identify the earliest material so that you can dismiss later material as saying something about the Church rather than about Jesus.
This is why it’s important for apologists to know about the Synoptic problem. Regardless which solution (if any) one thinks persuasive, apologists need to be able to interact with the kinds of arguments involved. Otherwise, they will be unprepared to deal with those who use the relationships among the Synoptics to discredit them.
From the perspective of faith, the matter is much less urgent. Knowing how the Synoptic Gospels were composed can help shed light on particular passages, but it is not necessary for a basic understanding of Jesus and his message. From a faith perspective, the Gospels are inspired by the Holy Spirit and are reliable records of Jesus’ life and teachings.
In other words, the Jesus of history is the Christ of faith.