The synoptic problem is the cornerstone of historical critical scholarship of the gospels. As a result, one's solution to the synoptic problem will influence one's exegesis, redaction criticism, and form criticism of the gospels as well as affect the quest for the historical Jesus, early church history, and even the text of the gospels. In German scholarship on the synoptic problem, it has become customary to classify synoptic theories according to the nature of the interrelationship between the synoptic gospels. A documentary relationship may be either direct or indirect. One example of direct dependence is the traditional Augustinian Hypothesis, which holds that Matthew was first, followed by Mark who used Matthew, and then by Luke who used both Matthew and Mark.
Some solutions are hybrids.
Not so fast. It is rare for two independent reporters of the same event to share more than a few words in common, but the synoptic gospels often feature a substantial number of agreements in their exact words. For example, in one passage about John the Baptist, Matthew and Luke agree for 61 out of 63 Greek words of a presumably Aramaic speech. Extensive agreement in order , especially in which the arrangement of material is not strictly chronological but topical or exhibiting some other creativity in presentation. In these cases, it is difficult to attribute the non-chronological but topical narration to independent reporting.