Scholars designated the hypothetical source behind the shared material in Matthew and Luke as “Q” because Quelle was the German term for source. Yet where did the traditions that were unique to Matthew or to Luke come from? B. H. Streeter introduced the letter “M” and “L” to represent these traditions, for obvious reasons, and treated them too as hypothetical written sources. Today, most scholars tend to think that Matthew and Luke were probably drawing on a variety of oral and written sources for their extra traditions (however, a defense of “L” as a single source can be found in Kim Paffenroth’s The Story of Jesus According to L which was critically reviewed in RBL).
To refresh our memory about some content labelled under “M”, check out the post on Q. It is curious that Luke would neglect some of these episodes if he read Matthew’s Gospel since they could align with Luke’s interest in unmerited grace and forgiveness, Gentiles, or economic matters. Austin Farrer had a theory: “Must we therefore distinguish in Matthew two elements, M and Q, M rabbinic in tone, Q popular and nonrabbinic, of which St. Luke knew Q, but not M? Will it not do as well to say that St. Luke let alone what he did not care for, viz., the rabbinic parts of Matthew?” (Austin Farrer, “On Dispensing with Q“, 58). This explanation does not really work given that the “L” material Luke preserves also features scriptural echoes, biblical proof-texts, and (anachronistically) “rabbinic” styles of argumentation. Proponents of the Farrer Hypothesis may have to concede that, in some instances, it is difficult to figure out why Luke copied some bits of Matthew’s text and not others.
Again, we can take up a specific example in the distinctive birth narratives in Matthew and Luke. It could be a remarkable coincidence that Matthew and Luke independently modified Mark’s account by adding a genealogy and birth story. However, at the Society of Biblical Literature meeting in Atlanta I attended both sessions on Francis Watson’s excellent book Gospel Writing: A Canonical Perspective (Eerdmans, 2013). In one session, Richard Burridge critiqued Watson for not taking more account of the genre of the Gospels as biographies (bioi, “lives”), for the ancestry and birth of a subject was standard fare for biographers. The names of Jesus’ parents, Mary’s miraculous conception, or the birth in Bethlehem where king David was born may derive from widespread oral traditions.
Nevertheless, Mark Goodacre (Case Against Q, 56-58) observes that Luke reproduces the key elements of Matthew’s birth narrative (virgin birth, Mary and Joseph, Bethlehem), replaces the gloom of Herod’s atrocity with the joy of Elizabeth and Mary or rejoicing angels and shepherds, and eliminates the Magi due to disliking magicians. Luke 1:31 even has verbatim agreement with Matthew 1:21 “and you will call the name of him Jesus,” even though these words do not fit well in Luke’s context in that they are addressed to the mother rather than the father who will name the boy. Francis Watson (Gospel Writing, 131-136, 141-143) sees Luke’s account as a reaction to Matthew: the verbal echoes of Matthew’s wording, the annunciation to Mary as the main subject rather than Joseph, the celebratory tone of Luke’s version, and the rejection of Matthew’s genealogy that traces Jesus’ descent through Solomon’s line (see Jeremiah 22:28-30; 36:30-31). What do you think?