Why does Matthew go over Joseph's lineage?

http://www.christadelphian-advocate.org/features/qbox/qbox51.html

The gospel of Matthew, it is commonly accepted, was written to the Jews, who were very interested in family heritage and legal entitlement. As such, Matthew presents the lineage of Jesus beginning with Abraham, through David the King to Joseph, the husband of Mary and legal, but not genetic, father of Jesus. The focus of Matthew's account is to provide us clear proof that Jesus was the legal heir to the throne of David and the promised Messiah through his lineage from David and Abraham. This we see emphasized in the opening verse, Matthew 1:1 "The book of the generation of Jesus Christ, the son of David, the son of Abraham."

The scriptures clearly state the claim of Jesus to the throne of David. One example is the instance when the angel spoke to Mary and told her, "And, behold, thou shalt conceive in thy womb, and bring forth a son, and shalt call his name JESUS. He shall be great, and shall be called the Son of the Highest: and the Lord God shall give unto him the throne of his father David: And he shall reign over the house of Jacob for ever; and of his kingdom there shall be no end." (Luke 1: 31-33)

A second example is Peter's address to those present at Pentecost, when he stated, "Men and brethren, let me freely speak unto you of the patriarch David, that he is both dead and buried, and his sepulchre is with us unto this day. Therefore being a prophet, and knowing that God had sworn with an oath to him, that of the fruit of his loins, according to the flesh, he would raise up Christ to sit on his throne." (Acts 2:29-30)

The oath sworn by God was given to David by the prophet Nathan and outlined the unconditional promise of perpetuity of the Davidic Kingdom. As recorded in 2 Samuel 7: 12-13, "And when thy days be fulfilled, and thou shalt sleep with thy fathers, I will set up thy seed after thee, which shall proceed out of thy bowels, and I will establish his kingdom. He shall build an house for my name, and I will stablish the throne of his kingdom for ever."

Two later royal representatives of that line of descent for which eternal perpetuity had been promised, who reigned at the time of the Babylonian Captivity, were Jehoiakim (also known as Eliakim) and his son Jeconiah (also known as Jehoiachin and Coniah). Jehoiakim, as recorded in Jeremiah 36, angered God by burning a scroll that Jeremiah the prophet wrote against Israel and against Judah for their idolatrous conduct. As a result, God cursed Jehoiakim, "Therefore thus saith the LORD of Jehoiakim king of Judah; He shall have none to sit upon the throne of David: and his dead body shall be cast out in the day to the heat, and in the night to the frost." (Jeremiah 36:30)

At the time of the initial Babylonian conquest of Jerusalem, this was literally fulfilled. One of his sons, Jeconiah, who was subsequently placed on the throne by the Babylonians, remained there for a mere three months. It is recorded of him, "And he did that which was evil in the sight of the LORD, according to all that his father had done. (2 Kings 24: 9) He was also cursed by God, "Thus saith the LORD, Write ye this man childless, a man that shall not prosper in his days: for no man of his seed shall prosper, sitting upon the throne of David, and ruling any more in Judah." (Jeremiah 22:30)

It is here that we have a problem to resolve. Both Jehoiakim and Jeconiah were ancestors of Joseph and also David's descendants through Solomon. It was through them that the Solomon descent and legal right to the throne of David properly should be traced. Solomon's throne had already been unconditionally promised eternal perpetuity. Yet both Jehoiakim and Jeconiah were cursed by God and told that they would have no physical descendants who would prosper on the throne of David. Without contradicting the divine curse, how could Jesus legally lay claim to the throne of David while God's promise to David that one of his physical descendants would reign on the throne forever also is fulfilled?

Jeremiah's account does not indicate that Jehoiakim or Jeconiah would have no seed. Jehoiakim had at least one other son, Zedekiah. Jeconiah had at least seven recorded sons, Salathiel and Pedaiah, being the two most noted. Nor does it indicate that the royal line through them had its legal claim to the throne of David removed. The legal claim to the throne remained with their line, and Mathew records that descent down to Joseph. In Matthew 1:16, Matthew preserves the virgin birth of Jesus and at the same time makes it clear that Jesus did not come under the curse upon Jehoiakim and Jeconiah. He breaks the pattern and carefully avoids recording that Joseph 'begat'. Instead he records, 'Joseph, the husband of Mary, of whom was born Jesus'. In the English translation the antecedent of 'whom' is ambiguous. In the Greek text, though, 'whom' is feminine singular in form and can refer only to Mary who was not a descendant of Jehoiakim and Jeconiah. As to human genetic parentage, Jesus was born of Mary alone. She was a descendant of Nathan, another son of David (Luke 3:31) and as the genetic mother of Jesus, fulfilled the prophetic scriptures of his being 'according to the flesh' and 'the seed of the woman' taught throughout the scriptures and confirmed by Jesus himself.

We have already noted Acts 2:30. Other examples are the following:

■"Concerning his Son Jesus Christ our Lord, which was made of the seed of David according to the flesh." (Romans 1:3)

■"But when the fulness of the time was come, God sent forth his Son, made of a woman, made under the law." (Galatians 4:4)

■" I Jesus have sent mine angel to testify unto you these things in the churches. I am the root and the offspring of David, and the bright and morning star." (Revelation 22:16)

Joseph was his legal father and as such, Joseph's legal inheritance, including a legal claim to the throne of David, passed to Jesus. Jesus was exempt from the curse of Jehoiakim and Jeconiah, however, because Joseph was not his genetic father.

In summary, we have a clear example of God's will being accomplished in seemingly impossible circumstances, demonstrating the veracity of His word. Through the circumstances of his birth, Jesus, by Joseph was granted a legal claim to the throne of David; by Mary, Jesus was the seed of David 'according to the flesh', thus maintaining the integrity of the curse God had pronounced upon Jehoiakim and Jeconiah.

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