The two-source hypothesis (or 2SH) is an explanation for the synoptic problem, the pattern of similarities and differences between the three Gospels of Matthew, Mark, and Luke.
The strengths of the hypothesis are its explanatory power regarding the shared and non-shared material in the three gospels; its weaknesses lie in the exceptions to those patterns, and in the hypothetical nature of its proposed collection of Jesus-sayings.
The two-source hypothesis was first articulated in 1838 by Christian Hermann Weisse, but it did not gain wide acceptance among German critics until Heinrich Julius Holtzmann endorsed it in 1863.
The Two-Source Hypothesis crossed the channel into England in the 1880s primarily due to the efforts of William Sanday, culminating in B. H. Streeter's definitive statement of the case in 1924.
Mark appears more 'primitive': his diction and grammar are less literary than Matthew and Luke, his language is more prone to redundancy and obscurity, his Christology is less supernatural, and he makes more frequent use of Aramaic.
[6] While the 2SH remains the most popular explanation for the origins of the synoptic gospels, two questions - the existence of the so-called "minor agreements," and problems with the hypothesis of Q - continue at the centre of discussion over its explanatory power.
Streeter devoted a chapter to the matter, arguing that the Matthew/Luke agreements were due to coincidence, or to the result of the two authors' reworking of Mark into more refined Greek, or to overlaps with Q or oral tradition, or to textual corruption.
Accordingly, some scholars (like Helmut Koester) who wish to keep Q while acknowledging the force of the minor agreements attribute them to a proto-Mark, such as the Ur-Markus in the Marcan Hypothesis (MkH), adapted by Mark independently from its use by Matthew and Luke.
The minor agreements are also, according to the critics, evidence of the non-existence of, or rather the non-necessity for, Q: if Matthew and Luke have passages which are missing in Mark (the "Who is it that struck you?"
[12] Some form of the Two Source hypothesis continues to be preferred by a majority of New Testament scholars as the theory that is best able to resolve the synoptic problem.
In 1965 an American scholar, William R. Farmer, also seeking to do away with the need for Q, revived an updated version of Griesbach's idea that Mark condensed both Matthew and Luke.
[13] In 1838, the German theologian Christian Gottlob Wilke argued for a solution that combined Marcan priority with an extensively developed argument for Matthew's direct dependence upon both Mark and Luke.
The Wilke hypothesis was accepted by Karl Kautsky in his Foundations of Christianity[14] and has begun to receive new attention in recent decades since its revival in 1992 by Huggins,[15] then Hengel,[16] then independently by Blair.