5.27 Evidence to Support the Two-Source Hypothesis

The Synoptic Puzzle

Analysis of parallel passages in the Synoptic Gospels yields the following data:

A large amount of parallel material is found in Matthew, Mark, and Luke.
A large amount of parallel material is found in Matthew and Luke, but not Mark.
Some parallel material is found in Matthew and Mark, but not Luke.
A small amount of parallel material is found in Luke and Mark, but not Matthew.

The question of how to explain these relationships is called the “Synoptic Puzzle” (or the “Synoptic Problem”).

The Two-Source Hypothesis

Mark was written first, and Matthew and Luke used Mark as a source.
Matthew and Luke were produced independently of each other.
Matthew and Luke also both used a now-lost collection of Jesus’s sayings, which scholars call “Q.”

The following points are often cited by supporters of the Two-Source Hypothesis as evidence for the validity of that theory.

Evidence That Matthew and Luke Used Mark as a Source

The significant overlap of material between Mark and the other two Synoptic Gospels suggests either (1) Mark used Matthew and/or Luke as a source, or (2) both Matthew and Luke used Mark. The latter seems more likely for these reasons:

Omission of Markan material from Matthew and Luke is more explicable than is omission of Matthean and Lukan material from Mark.

Matthew and Luke may omit Mark’s reference to being “salted with fire” (Mark 9:49) because the expression is not easy to understand, or they may omit Mark’s story of the fleeing young man (14:51) because it seems irrelevant. But why would Mark omit the Lord’s Prayer, the Beatitudes, or the story of the good Samaritan, much less stories of Jesus’s birth or of his resurrection appearances?

Divergences in Matthew and Luke from the sequence of material in Mark are more explicable than are divergences in Mark from the sequence of material in Matthew or Luke.

Miracles scattered throughout the first half of Mark are gathered together in Matthew 8–9, providing a topical “miracle section” comparable to the preceding “teaching section” in Matthew 5–7; the story of Jesus’s rejection in Nazareth in Mark 6:1–6 is moved forward in Luke (4:16–30) because a hometown story makes logical sense before stories of his ministry elsewhere and because the story introduces the rejection of Jesus as a programmatic theme to be developed in the narratives of the ministry that follows. If we were to assume that Mark was copying from Matthew or Luke, the rationale for his altering their sequence of such events would be difficult to comprehend.

Minor differences of language or fact are better understood as Matthean or Lukan improvements of Mark rather than as Markan corruptions of Matthew and Luke.

Greek syntax and grammar are more colloquial in Mark and more refined in both Matthew and Luke. For example, Herod is incorrectly called a king in Mark 6:14 but is correctly called a tetrarch in Matthew 14:1.

Numerous inconsistencies in Matthew and Luke are more explicable on the premise that they use Mark as a source than they would be otherwise.

Matthew actually does call Herod a king in 14:9 but a tetrarch everywhere else because at 14:9 he is following Mark (6:26) and neglected (this time) to correct his source; Luke 4:23 speaks of miracles in Capernaum that haven’t happened yet (cf. Luke 4:31–37) because Luke bases the story in 4:16–30 on Mark 6:1–6, which in Mark’s Gospel does come after the account of the Capernaum miracles (Mark 1:21–28; 2:1–12).

Evidence That Matthew and Luke Were Produced Independently of Each Other

With regard to sequence of events, Matthew and Luke frequently agree with each other and with Mark, but they rarely agree with each other against Mark. This suggests that Mark served as a basic outline used independently by both Matthew and Luke, who sometimes followed him and sometimes did not. If (as an alternative proposal suggests) Mark had copies of both Matthew and Luke and produced an abbreviation of their works, we would expect instances in which Mark departed from a sequence of events followed by both Matthew and Luke.

Neither Matthew nor Luke includes the other’s major additions to the Markan text.

Matthew’s additions to Mark’s story of the temple cleansing are not found in Luke (Mark 11:15–19; Matt. 21:12–17; Luke 19:45–48); Luke’s additions to Mark’s story of Jesus’s transfiguration are not found in Matthew (Mark 9:2–8; Luke 9:28–36; Matt. 17:1–13).

The likelihood that either Matthew or Luke used the other as a source is reduced by what would then be inexplicable omissions of material.

The story of the sheep and goats is found in Matthew (25:31–46) but not in Luke, though it would fit well with Luke’s characteristic concern for the poor; the parable of the Pharisee and the tax collector is found in Luke (18:9–14) but not in Matthew, though it would fit well with Matthew’s polemic against the Pharisees.

The material that Matthew and Luke have in common but that is not found in Mark is not found at the same place in their Gospels.

For example, Matthew places the woes against the Pharisees near the end of his Gospel, during the last week of Jesus’s life (23:13–36); Luke places them around the middle of Jesus’s ministry, while he is still in Galilee (11:37–12:1). This suggests that Matthew and Luke are independently using material from another source (Q); if Matthew were using Luke or if Luke were using Matthew, we would expect material that they have in common (but that is not found in Mark) to come at the same place in their Gospel stories.

Evidence for the Existence of Q as an Additional Source

Matthew and Luke have a great deal of material in common that is not found in Mark’s Gospel. If they did not derive this material from Mark, and if neither of them derived it from the other, the logical conclusion is that they derived it independently from some additional source. This conclusion is bolstered by the following observations:

The non-Markan material that Matthew and Luke have in common exhibits strong verbal agreement. The two Gospels often say exactly the same thing, displaying more word-for-word correspondence than in passages that they have derived from Mark.
The non-Markan material that Matthew and Luke have in common often is presented in the same general sequence. This suggests that they are inserting material from an additional source into the basic Markan story (though, as indicated above, they never insert this material in exactly the same places in the Markan story).
The non-Markan material that Matthew and Luke have in common exhibits a high degree of linguistic and theological consistency, suggesting that it came from a single, coherent document.