What on Earth is 'Q'?

The Quest for a Lost Gospel Source

At the heart of gospel studies lies a problem: the Synoptic problem.

It is called synoptic because Matthew, Mark and Luke can be ‘seen together’ (syn-opsis). They feature a lot of the same material. It is a problem because no one is entirely sure why they share this material.

The simplest starting point is to express what everyone is pretty sure about: Mark was written first, and Matthew and Luke both seem to have read Mark and copied out a lot of its material. But beyond this, the picture gets very complicated.

There is lots of material which Matthew and Luke themselves share which is not found in Mark. So how do we explain the relationship between Matthew and Luke? Did one of them copy from one another? Or were they were copying independently from another source?

The majority of gospel scholars solve this next step with the latter move. They hypothesise another source, which was given the rather enigmatic title, ‘Q’, an abbreviation of German word for source (Quelle).

With these two sources in place, we have what gospel scholars refer to as the ‘two source hypothesis’. Matthew and Luke both used Mark (source one), and they also both used a text called Q (source two), but they didn’t use each other.

We therefore end up with a map of the problem which looks something like this:

The question I want to answer in this post is simple: why believe in Q? Why think that there was a hypothetical source which is now lost to the sands of time? And what is at stake if we do?

Why Believe in Q?

At first glance, ‘Q’ may seem completely superfluous. If Matthew and Luke have the same material, why could one of them have not copied from the other? In this way, we could explain their common material without reference to an additional source.

However, advocates of Q argue that there is good evidence that Matthew and Luke did did not copy each other. The argument for Q is therefore almost entirely an argument for Mathean and Lucan independence. The question becomes: What reasons do we have to think that Matthew and Luke are independent? Let us look at a few.

One serious consideration is that Matthew and Luke rarely place their ‘Q’ material in the same location. This is particularly surprising since the locations in which Matthew places his material are often very appropriate. It is strange that Luke – often considered the later source – did not make use of Matthew’s placement of material.

Take Matthew’s sermons, which are scattered throughout Luke. Why has Luke decided to break up Matthew’s organised material? Perhaps he had some reason to organising the material when did. But a simpler explanation seems to be that Matthew and Luke had a common source and did different things with it.

Another observation is that Luke fails to use Matthew’s additions to Mark. Luke tend to use Mark as it is, rather than Mark as Matthew knew it. For Q theorists, this is evidence that Luke didn’t know Matthew’s additions. He simply knew Mark as it was.

We might also find support for Q in the discovery of a similar text: The Gospel of Thomas. Like the Q source, the so-called Gospel of Thomas is not a narrative but a collection of sayings of Jesus. This lent support to the idea that a ‘Q’ like source could have existed and been lost to posterity, since Thomas was only recovered in 1945.

Why Doubt Q?

These may seem like some pretty good reasons to believe in Q. But not everyone is convinced. Since the late twentieth century, a growing number of scholars have questioned whether Q is the best explanation of the evidence.

Austin Farrer, a gospel scholar at Oxford (and good friend of C.S. Lewis) wrote an influential article called, “On Dispensing with Q.” This paper argued that we can get rid of Q by supposing that Luke relied upon Matthew. As Farrer puts it, Q “wholly depends on the incredibility of St Luke having read St Matthew's book.”¹

Since Farrer, a significant minority of scholars have come to doubt the existence of Q . In particular, Michael Goulder developed Farrer’s arguments, and their work has been defended prodigiously by Mark Goodacre as the ‘Goulder-Farrer’ thesis.

Goodacre makes the following general arguments against the existence of Q:²

1. Many of the differences between Matthew and Luke can be accounted for by Luke’s own reasons to break up or omit the material found in Matthew. To provide just one example, Luke may not have wanted to include ‘magi’ in his birth story, given his own anti-magical proclivities (cf. Acts 19:9).

2. Luke has engaged in a similar project to Matthew. He has used Mark, his own separate material, and added a birth story and his own resurrection narrative. This creates an intriguing dilemma. If Luke and Matthew wrote at the same, the odds of them both engaging in such a similar project are slim. But the later one leaves it before Luke wrote, the higher the chances that he knew Matthew. Certainly, Luke claims to know ‘many other’ accounts like it (1:1-4).

3. There are some instances in which Luke and Matthew agree against Mark. The most striking example of this is in their passion material, in which Matthew and Luke both contain the phrase, ‘Who is it that struck you?’, during Jesus’ mockery. If Q did not contain any direct material on the death and resurrection of Jesus, as most suppose, it looks like one of the evangelists has copied from the other.

Of course, how convincing one finds either set of arguments is subjective, to an extent. Some scholars will find a very clear method in the apparent madness of breaking up Matthew’s material; others point to text-critical explanations of some of this data; others still prefer more complex models (like Maurice Casey’s ‘Chaotic Q’.)³ What is crucial to recognise is that the debate is alive and well.

Why Does it Matter?

We might conclude this précis by asking: what is at stake in the Q debate?⁴

For some scholars, it nothing less than the history of Christian origins. For them, Q represents a window into an alternative Christianity, in which it is Jesus’ teaching, rather than his death and resurrection, which lies at the centre of life and faith.

On this model, we are often told that it possible to peel back the layers of Q. In doing so, we arrive at an historical Jesus who was not an apocalyptic prophet, expecting the imminent arrival of God’s Kingdom, but a dispenser of sapiential sayings.

Yet this kind of reconstruction makes a couple of suspicious moves. For a start, it assumes that we are capable, at great remove, of working out layers of redaction within an already hypothetical source document. To embark on this exercise with any modicum of confidence is beyond me, and I suspect it is beyond us all.

But then to assume that ‘Q’ offers us a window into a revisionist portrait of a non-apocalyptic Jesus and Jesus-movement is an even greater stretch. Putting aside the strong evidence that both Jesus and his followers were apocalyptically-orientated, it simply does not follow that Q should be read as the sole document for a Christian community detached from the wider body of thought and praxis.

Assuming its existence, we know that at least two authors (Matthew and Luke) had no qualms integrating Q into their work. This reduces the likelihood that they saw Q as representing a thread of Jesus tradition which differed substantially from their own.

My own sense of Q’s significance is not that it is a magic portal into a lost Christianity behind the Gospels, but that it is an important source for the historical Jesus. It is generally taken to pre-date 70 CE, and (as I shall explore in a future post) a number of scholars believe it is already assumed in the letters of Paul.

Finally, if Q did exist, it would show that Matthew and Luke were interested – much like other biographers – in relying upon source material (not only Mark, but Q), and it would betray their own interests in shaping that shared material as they did.

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1. There are a number of reasons why scholars assume that Luke would have used Matthew, rather than the other way round. Not least, Luke seems to have knowledge of former narratives like his (1:1-4).

2. In addition to episodes on Mark Goodacre’s podcast, the NT Pod, see his classic work, The Case Against Q: Studies in Markan Priority and the Synoptic Problem (Leiden: Brill, 1999).

3. Rather than seeing ‘Q’ as a simple Greek document, Casey and others have thought that parts of Q were originally written in Aramaic (by the apostle Matthew) and were later translated into Greek by the evangelists. For a summary of this idea, see here.

4. My thoughts below are heavily indebted to Dale C. Allison, “The Eschatology of Jesus” in The Encyclopaedia of Apocalypticism, vol. 1, eds. John J. Collins, et al. (New York: Continuum), 267-302.