Why does Matthew's gospel begin with Jesus' genealogy?
Matthew begins with Jesus’ genealogy to prove He is the rightful heir to David’s throne. By identifying Him as the son of David and son of Abraham, the genealogy establishes His legal lineage for the kingdom over which the King of kings will rule.
Les explains that Matthew’s opening genealogy is given in light of the covenant’s third part—the government, the king. The New Testament introduces Jesus genealogically to show He is the rightful heir to the throne of David. Matthew 1:1 calls Him “the son of David, the son of Abraham,” and the genealogy stops there because its purpose is to prove His royal claim as a son of David through the family tree. By contrast, Luke 3 traces Mary’s genealogy back to Adam, while Joseph, though not Jesus’ physical father, was His legal father; the lines branch at Solomon, one forming Mary’s genealogy and the other Joseph’s.