Focusing his exploration on Jesus' Five Discourses, Scaer demonstrates that Matthew was written as catechesis, a method in concert with its content and organization. The discourses summarize the message the disciples are to carry to "all nations" and each discourse builds on its predecessors to culminate in the narrative of Jesus' death and resurrection, which is the Gospel's interpretive key.
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Although scholars may differ on the precise beginnings and endings of Matthew's Five Discourses, they can be divided in this way: (1) the Sermon on the Mount, Matt 5:1-7:28a; (2) apostolic authority and martyrdom, Matt 9:35-11:1; (3) the parables, Matt 12:46-13:53; (4) casuistry, or resolving incidental matters of church practice, Matt [17:22] 18:1-19:1; and (5) the end times, Matt 23:1-26:1. These divisions are determined by their similar conclusions- "When Jesus had finished"-and are brought together by the Gospel's conclusion: "teaching them to observe all that I have commanded you" (28:20). Each discourse is a self-contained unit, but the meaning of each is related to and dependent on the others. No single discourse can be understood by itself without the possibility of misinterpretation.