Son Of David

In the Old Testament, the Messiah was expected to be a descendant of David (2 Samuel 7:8-16, Psalm 89:3-4, 132:11-12, Isaiah 11:1, Jeremiah 23:5, 33:15). And later Jewish tradition was expecting a Davidic Messiah:

"Although there was much diversity in messianic speculation among individual Jewish groups, a general consensus emerged within later Judaism that the Messiah would be Davidic along the lines set out by the exilic prophets. A representative statement of Jewish messianic expectations is Psalms of Solomon 17-18…Essentially the same description of the Davidic Messiah appears at Qumran (1QM 11:1-18; 4QFlor 1:11-14; 4QPBless 1-7; 4Qtestim 9-13; see Dead Sea Scrolls) and in the Pseudepigrapha (4 Ezra 12:31-32; T. Jud. 24:1-5)." (D.R. Bauer, in Joel B. Green, et al., editors, Dictionary of Jesus and the Gospels [Downers Grove, Illinois: InterVarsity Press, 1992], p. 767)

Many early Christian sources refer to Jesus as a descendant of David (Matthew 1:1, Mark 10:47-48, Luke 1:32, Romans 1:3, Revelation 22:16), and Jesus seems to have accepted the claim (Matthew 12:22-32, 15:21-28, 21:1-16, Mark 10:46-52, 12:35-37). Since relatives of Jesus were available to and prominent in the early church and since some genealogical records were kept among the Jews of the first century, the early Christian accounts of Jesus’ being a descendant of David seem credible. Some of the earliest Christians had been active in the leadership of Judaism during the early stages of Christianity (Acts 6:7, Philippians 3:4-6), so they probably would have heard of objections to Jesus' Davidic ancestry if there were any. Paul, for example, was active in persecuting the church and surely would have had significant knowledge of the arguments used against Christianity by the earliest opponents of the movement, and he was in contact with Jesus' immediate family. He affirms Jesus' Davidic descent (Romans 1:3, 2 Timothy 2:8). How could Jesus' claim to be the Messiah have gotten far among so many people who had the expectation of Davidic descent, and why would He have even thought of Himself as such a Messiah in the first place, if He wasn’t descended from David? As the author of Hebrews indicates, information on Jesus’ background was "evident" to the public (Hebrews 7:14). Raymond Brown referred to Jesus' Davidic descent as accepted by "the majority of scholars" (The Birth Of The Messiah [New York, New York: Doubleday, 1999], p. 505). Craig Keener writes:

"there is little doubt that Jesus’ family historically stemmed from Davidic lineage. All clear early Christian sources attest it (e.g., Rom 1:3); Hegesippus reports a Palestinian tradition in which Roman authorities interrogated Jesus’ brother’s grandsons for Davidic descent (Euseb. H.E. 3.20); Julius Africanus attests Jesus’ relatives claiming Davidic descent (Letter to Aristides); and, probably more significantly, non-Christian Jewish polemicists never bothered to try to refute it (Jeremias 1969: 291). Jesus’ relatives known in the early church seem to have raised no objection to the claim of their family’s background (Brown 1977: 507)….B. Sanh. 43a, bar., may preserve a [non-Christian Jewish] tradition that Jesus was of royal lineage (unless it suggests connections with the Herodian or Roman rulers, or that he was about to take control of the people; both views are unlikely)." (A Commentary On The Gospel Of Matthew [Grand Rapids, Michigan: William B. Eerdmans Publishing Company, 1999], p. 75 and n. 9 on p. 75)

D.A. Carson writes:

"After Zerubbabel [in Matthew’s genealogy], Matthew relies on extrabiblical sources of which we know nothing. But there is good evidence that records were kept at least till the end of the first century. Josephus (Life 6 [1]) refers to the 'public registers' from which he extracts his genealogical information (cf. also Jos. Contra Apion I, 28-56 [6-10]). According to Genesis R 98:8, Rabbi Hillel was proved to be a descendant of David because a genealogical scroll was found in Jerusalem. Eusebius (Ecclesiastical History 3.19-20) cites Hegesippus [a second century Christian] to the effect that Emperor Domitian (A.D. 81-96) ordered all descendants of David slain. Nevertheless two of them when summoned, though admitting their Davidic descent, showed their calloused hands to prove they were but poor farmers. So they were let go. But the account shows that genealogical information was still available. While no twentieth-century Jew could prove he was from the tribe of Judah, let alone from the house of David, that does not appear to have been a problem in the first century, when lineage was important in gaining access to temple worship." (The Expositor's Bible Commentary: Matthew, Chapters 1 Through 12 [Grand Rapids, Michigan: Zondervan, 1995], p. 63)

Though the New Testament emphasis is on the Davidic lineage of Joseph, there was widespread early belief that Mary was a descendant of David as well. Gabriel is speaking with Mary in Luke 1:32, and Joseph isn't mentioned in the immediate context, so a Davidic descent of Mary may be in view, though Joseph is mentioned in verse 27. The concept of Mary's Davidic descent seems to be popular in second century sources as early as Ignatius of Antioch (Raymond Brown, et al., editors, Mary In The New Testament [Mahwah: Paulist Press, 1978], pp. 260-261), though the evidence isn't as significant as it is for Joseph's ancestry. Whatever Mary's ancestry was, it seems that Jesus' status as a descendant of David was considered sufficiently credible to gain general acceptance among the early Christians and their early opponents.