Herbert Marsh, an Englishman, is seen by some as the first person to hypothesize the existence of a "narrative" source and a "sayings" source, although he included in the latter parables unique to Matthew and unique to Luke [REF].
In 1838 another German, Christian Hermann Weisse, took Schleiermacher's suggestion of a sayings source and combined it with the idea of Markan priority to formulate what is now called the Two-Source Hypothesis, in which both Matthew and Luke used Mark and the sayings source.