Tom Dyskstra on 'Q' -
... the Apostle [Paul] records almost nothing of his Lord’s life and sayings40 ...
Some scholars postulate the existence of a written document they call Q which preserved a substantial series of Jesus’ sayings, and which might have been written down before Mark.41
According to this hypothesis, Matthew and Luke were each ignorant of the other’s gospel but each used Mark and Q as their sources, and so Q can be reconstructed from areas where the text of Matthew and Luke is identical without a counterpart in Mark. But no physical remnants of Q have ever been found, no ancient writer clearly mentions the existence of such a document,42 and even Q’s advocates assume it was not written down until, as in the case of Mark, decades had elapsed after the words recorded were originally spoken.
Remnants of non-canonical gospels such as the Gospel of Thomas have survived, but none of the surviving manuscripts can be dated earlier than the second century. While a few scholars assign a first-century date to the original version of Thomas, here too even the most optimistic among them do not propose that the sayings were committed to papyrus at the time when the recorded words were spoken.
The most plausible conclusion is that there were no written records of Jesus’ life and sayings earlier than Mark ...
Dykstra, T (2012) Mark, Canonizer of Paul, OCABS Press; St Paul, Minnesota 55124: Chapter 3.
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40 For a complete list of everything in Paul's epistles that cites sayings of Jesus or can be interpreted as alluding to such sayings, see Nikolaus Walter, “Paul and the Early Christian Jesus-Tradition,” in A. J. M. Wedderburn, ed., Paul and Jesus: Collected Essays (Sheffield: JSOT Press, 1989), 51-80.
41 For an exposition of the Q theory, see James M. Robinson, Jesus: According to the Earliest Witness (Minneapolis: Fortress Press, 2007). For a proposed reconstruction of Q, see Paul Hoffmann, John S. Kloppenborg, and James M. Robinson, eds., The Critical Edition of Q: A Synopsis Including the Gospels of Matthew and Luke, Mark, and Thomas with English, German, and French Translations of Q and Thomas (Minneapolis: Fortress Press, 2000). And for arguments that nothing like Q ever existed, see Mark Goodacre, The Case Against Q: Studies in Markan Priority and the Synoptic Problem (Harrisburg: Trinity Press International, 2002) and Mark Goodacre and Nicholas Perrin, eds., Questioning Q: A Multidimensional Critique (Downers Grove: InterVarsity Press, 2004).
42 Eusebius quotes a certain bishop Papias of Hierapolis as mentioning a compilation of sayings of Jesus that was used by Matthew, and some scholars take this to be a reference to Q. Most, however, interpret Papias’ comments as referring to the canonical book of Matthew.
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