Farrer on the Matthean context of double tradition

The story of the Centurion is commonly supposed to have been derived by St Matthew from Q. But surely the moral to be drawn from the extraordinary neatness with which the story nestles into its Matthaean context is that it was cast into written form for the first time by the man who placed it in that context, that is, by St Matthew himself. St Luke re-shapes the story somewhat, but even so it has no such vital or manifold connexions with the context in which he places it. The same is true of several other pieces of the so-called Q tradition: they appear to be made for their Matthaean place, and adjusted to their Lucan place. The fact is admitted by the friends of the Q hypothesis and actually twisted into an argument in support of it. St Luke, they say, could never have found his material in St Matthew, or he would not have dreamt tearing it from the perfect setting it there has, to place it less happily in his own Gospel. It is wiser to say: St Luke, wishing to write his own book in his own way, re-arranged his material he found in his authors. He did it skilfully, but no amount of skill could make an adapted context fit as tight as the context for which the material was composed.

Austin Farrer, St Matthew and St Mark (The Edward Cadbury Lectures, 1953-4; Westminster: Dacre Press, 1954), 46-7, n.2