Well, with Walton and Wenham's introduction, there is good news for Q sceptics: the Farrer theory is treated in its discussion of the Synoptic Problem including its own diagram, brief discussion, and bibliographical references to Farrer's article, my introductory book (Way through the Maze), my monograph (Case Against Q) and even the NT Gateway (70, 73, 87). Although it is naturally disappointing to see them dismiss the theory as having "many of the same objections as the Griesbach hypothesis" leading to the view being "not very widely held" (73), it is nevertheless encouraging to see the theory finding its way -- at last -- into the introductory literature.
What, though, of the substance of their exploration of the Synoptic Problem? There are several reasons to find it refreshing. For one thing, there is some discussion of the data before there is any discussion of the proposed solutions (61-5) echoing even those who like me who advocate the colouring of the Synopsis (62, though I think that students will find my primary colour scheme more straightforward than their four-colour scheme). For another, there is one sample synopsis (63, Sadducees' Question) and several lists taken over from Robert Stein's book (64, 68, 69) and one from Sanders and Davies (72).
Regular readers will not be expecting me to be unambiguously positive, though, and I don't want to disappoint them. I would like to focus on a couple of difficulties in the discussion, the first with the way that they treat the Griesbach or Two Gospel (not "Two Gospels", 71) Theory. Walton and Wenham offer several criticisms of the hypothesis, most of them well sustained, but the following criticism does not conceptualize the Griesbach theory fairly:
Luke's rearrangement of Matthean material Consider the material shared by Matthew and Luke, but not found in Mark (the Q material on the two source hypothesis). Apart from rare examples (such as the temptation of Jesus, Matt. 4.1-11; Luke 4.1-13), Luke and Matthew do not present this material in conjunction with the same Markan material, but locate it in different settings in their Gospels. In fact, on the Griesbach hypothesis, in editing Matthew, Luke has systematically moved almost all this material from its Matthean contexts to somewhere else in his Gospel. This seems unlikely: a better explanation is that Luke is using Mark as a main source and other material to supplement Mark (73).The difficulty with this explanation is that on the Griesbach Hypothesis, Luke is writing without reference to Mark, before Mark has been written, so the distinction between "Markan material" and "Q material" is irrelevant. There is no option, then, for Luke and Matthew to present this material "in conjunction with the same Markan material". For Griesbach's Luke, the distinction between double tradition and triple tradition does not exist. This means that on the Griesbach hypothesis, Luke often follows Matthew's order; it is just that he does so most recognizably in the material that we call triple tradition.
On the Griesbach hypothesis, this material becomes "triple tradition" by virtue of Mark's subsequent action, according to which Mark shows preference for material that is in the same order in his sources Matthew and Luke. In other words, it is an important element in the Griesbach hypothesis that Mark effectively creates the triple tradition by his selections from Matthew and Luke, a selection that is at least partly done on the basis of Matthew's and Luke's agreements in order. Under such circumstances, it is a little unfair to criticize the theory for failing to explain Luke's ordering of double tradition. The data set double tradition is generated by a subsequent move made by Mark, partly on the basis of the question of order, and not by Luke's editorial decisions.
The second difficulty I would like to mention also relates to the question or order, but this time for the Farrer Theory. Griesbach is presented as the major alternative to the Two-Source theory (71-3) and Farrer is given a paragraph at the end under "Other Views". It is dismissed in one sentence as follows:
This view faces many of the same objections as the Griesbach hypothesis, for it still holds that Luke has edited Matthew in ways that appear hard to understand and this has meant that, like the Griesbach view, it is not very widely held (73).I disagree, of course, that it is hard to understand Luke's editing of Matthew, and it may be that Walton and Wenham's difficulty arises from their conceptualizing this work under the heading of criticizing the Griesbach hypothesis. So let's take a look at what they say on the topic when they are discussing Griesbach:
Why does Luke break up Matthew's teaching blocks? As we saw, Luke has most of the teaching found in Matthew's sermon on the mount (Matt. 5-7), but spread around his Gospel (see p. 69), and something similar happens with Matthew's four other teaching discourses (Matt. 10, 13, 18, 24-25). If Luke is using Matthew, this seems unusual behaviour. (72).On the Farrer theory, though, Luke's primary source for the structuring of his Gospel is Mark and paying careful attention to the way that Luke works with Mark helps to explain his use of Matthew. His attitude towards lengthy discourses in his source material is consistent, and we would not expect him to retain all of Matthew's huge, theme-based structures when we can observe him reworking material in a plausible, biographical narrative (Case, chapters 4, 5 and 6; Maze, 123-8).
Take, for example, the third of the big Matthean discourses listed by Walton and Wenham, Matthew 13. Matthew 13, the parable chapter, is a massively expanded version of Mark's parable discourse in Mark 4.1-34. Luke's parallel, in Luke 8.4-18, is a greatly reduced version of Mark 4, less than half its length, omitting some material and redistributing the rest. Given that Luke here halves the length of Mark's version of the very discourse in question, it is hardly "unusual behaviour" to see him behaving in the same way towards Matthew's expansion of it (cf. Walton and Wenham's chart on 72 that nicely illustrates Matthew's expansion and Luke's reduction of Matt. 4).
One last issue. One of the things I like about Walton and Wenham's chapter is that it encourages students to pay careful attention to the Gospel Synopsis, and they provide an example of one themselves on 63, the Sadducees' Question. Their English translation, however, masks an issue that is often missed, a telling minor agreement. They have Matt. 22.27, "Last of all, the woman herself died", Mark 12.22, "Last of all, the woman herself died" and Luke 20.32, "Finally, the woman also died". But Matthew and Mark are not identical here. Matthew has ὕστερον ⲉδὲⲉ̅̅ⲉ̅ⲉⲭⲛ πάντων . . . whereas Mark has ἔσχατον πάντων . . . Luke follows Matthew and not Mark with his ὕστερον. Why is this worth mentioning? Because ὕστερον is 7/0/1+0, seven times Matthew, never Mark, only here in Luke-Acts. It is Matthew's way of representing the last in a series. It's one of those nice minor agreements that illustrates Luke's knowledge of Matthew in triple tradition.

