Matthew's main purpose is to prove to his Jewish readers that Jesus is their Messiah.

He does this primarily by showing how Jesus in his life and ministry fulfilled the OT Scriptures. Although all the Gospel writers quote the OT, Matthew includes nine proof texts unique to his Gospel (1:22-23; 2:15; 2:17-18; 2:23; 4:14-16; 8:17; 12:17-21; 13:35; 27:9-10) to drive home his basic theme: Jesus is the fulfillment of the OT predictions of the Messiah.

Matthew even finds the history of God's people in the OT recapitulated in some aspects of Jesus' life.

To accomplish his purpose Matthew also emphasizes Jesus' Davidic lineage.

The fivefold division may suggest that Matthew has modeled his book on the structure of the Pentateuch (the first five books of the OT). He may also be presenting the gospel as a new Torah and Jesus as a new and greater Moses.