Gospel According to Mark, 2 in the Bible Encyclopedia - ISBE

VI. Sources and Integrity. We have seen that, according to the testimony of the Fathers, Peter's preaching and teaching are at least the main source, and that many features of the Gospel support that view. We have seen, also, subtle but weighty reasons for believing that Mark added a little himself. Need we seek further sources, or does inquiry resolve itself into an analysis of Peter's teaching? B. Weiss believes that Mark used a document now lost containing mainly sayings of Jesus, called Logia (L) in the earlier discussions, but now commonly known as Q (Quelle). In that opinion he has recently been joined by Sanday and Streeter. Harnack, Sir John Hawkins and Wellhausen have sought to reconstruct Q on the basis of the non-Markan matter in Matthew and Luke. Allen extracts it from Matthew alone, thinking that Mark also may have drawn a few sayings from it. Some assign a distinct source for Mark 13. Streeter considers it a document written shortly after the fall of Jerusalem, incorporating a few utterances by Jesus and itself incorporated bodily by Mark. Other sources, oral or written, are postulated by Bacon for smaller portions and grouped under X. He calls the final redactor R--not Mark but a Paulinist of a radical type. In forming a judgment much depends upon one's conception of the teaching method of Jesus and the apostles. Teaching and preaching are not synonymous terms. Matthew sums up the early ministry in Galilee under "teaching, preaching and healing," and gives us the substance of that teaching as it impressed itself upon him. Mark reports less of it, but speaks of it more frequently than either Matthew or Luke. Jesus evidently gave teaching a very large place, and a large proportion of the time thus spent was devoted to the special instruction of the inner circle of disciples. The range of that instruction was not wide. It was intensive rather than extensive. He held Himself to the vital topic of the kingdom of God. He must have gone over it again and again. He would not hesitate to repeat instructions which even chosen men found it so difficult to understand. Teaching by repetition was common then as it is now in the East. The word "catechize" (katecheo) implies that, and that word is used by Paul of Jewish (Rom 2:18) and by...

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