The genealogy in Matthew 1 is that of Joseph, Mary's husband, recorded for legal purposes to prove to the Jews that Jesus is the Messiah. Legally, the Jews of Jesus' day regarded Jesus as a son of Joseph. Joseph's lineage emphasizes the virgin birth, as a curse on one of his ancestors, Jechonias, prevented any natural descendant from sitting on the throne of David. According to Jewish usage, Mary's ancestry in Luke 3 is given under Joseph's name, indicating he was of Heli, likely Mary's father, making Joseph his son-in-law. Through marriage to Mary, Joseph inherited the right to rule on David's throne as Heli's heir, a right which then passed to Jesus. Joseph's genealogy shows that Christ was a legal descendant of Jechonias and thus could not inherit the throne solely through Joseph, further supporting the necessity of the virgin birth. Jesus inherits the right to rule over Judah through Mary's marriage to Joseph, whose lineage confirms his status as Heli's son-in-law.

Joseph, the step-father of Jesus Christ, plays a significant role in the genealogical records that affirm His lineage. In the account of Luke 3, the genealogy is most reasonably understood as tracing Jesus' biological descent through Mary, with Joseph noted as being of Heli, likely indicating a legal or marital connection rather than direct biological descent. This is supported by interpretations suggesting Joseph was the son-in-law or legal son of Heli, aligning with the customs of the time where inheritance and descent were traced through the male line. This lineage through Mary emphasizes Jesus' humanity and universality, connecting Him to all mankind, as Luke's gospel was written primarily for Gentiles. Meanwhile, the genealogy in Matthew 1 provides another line of descent, and together, these two separate lines to David strengthen Jesus' claim to the throne of David, fulfilling the vital connection to David's name in messianic terms.