How did Mark's Gospel influence the Gospels of Matthew and Luke?

Most biblical scholars agree that the Gospel According to Mark served as a foundational source for the authors of the Gospels of Matthew and Luke. This consensus, known as the "two-source hypothesis," posits that Mark provided the structural framework and narrative pattern for both later accounts.123

The influence of Mark is evident in several ways:
* Content Sharing: More than 90 percent of Mark’s content appears in Matthew, and more than 50 percent is incorporated into Luke.14
* Structural Patterning: Matthew and Luke generally follow Mark’s sequence of events. Literary analysis shows that where Matthew and Luke introduce material not found in Mark, it is typically inserted into different places, reinforcing the view that Mark served as the primary patterning form.43
* Refinement: Mark was written in a plain, sometimes crude Greek style with frequent use of Aramaic expressions and Latinisms. Matthew and Luke often "improved" this vernacular style in their own compositions.5

While Mark provided the narrative backbone, Matthew and Luke also share additional material—largely sayings of Jesus—that is absent from Mark, leading scholars to hypothesize the existence of a separate, lost source known as Q.24