Markan Priority is the view that many (=most) scholars hold that the gospel of Mark was composed first and that Matthew and Luke used Mark as their source material. The material that is NOT in Mark that is found in both Matthew and Luke can be found from a "hypothetical" source called "Q" (from German: Quelle [meaning "source"]). Essentially, this comes from a presupposition and an underlying assumption that the gospel writers could not have written their gospels independently from each other. The assumption is that because the synoptics (Matthew, Mark, and Luke) are so similar in many respects that there had to be some inner-dependence between them. But, again, this is an assumption and, in my estimation, a assumption that is unpersuasive. I hold that all three synoptics (Matt, Mark, and Luke) were written independently of each other and that the Holy Spirit sovereignly guided each of their hands as they wrote. The overwhelming similarities between them just shows how powerful and precise the Holy Spirit's guidance is over the author's writing of Scripture.
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Though I reject Markan priority for a host of reasons, I appreciate what Papias, an early 2nd century Christian wrote regarding the Gospel of Mark:
"Mark, having become the interpreter/translator of Peter, wrote down accurately, however, not in order, all that he recalled of what was either said or done by the Lord. For he had neither heard nor followed the Lord; but later (as I said) he followed Peter, who used to adapt his instructions to the needs (of the moment or of the audience), but not with a view of making an orderly account of the Lord's sayings (logia). Accordingly, Mark did no wrong in thus writing down some things as he recalled them, for he made it his aim to omit nothing he had heard and to state nothing therein falsely" (Raymond Brown, Introduction to the New Testament, 158).
