Matthew took great pains to prove Jesus’ lineage was through Joseph, to prove He was of the ‘Scion of David‘–the Messiah. Yet Matthew says Jesus was conceived by the Holy Spirit. How do you account for this? Who was Jesus’ father?
You are correct in stating that Jesus was conceived by the Holy Spirit. Matthew records that Mary was “found with child of the Holy Spirit” (Matt. 1:18), hence Jesus was truly the child of God. Luke confirms this by recording the words of the angel, “Therefore, also, that Holy One who is to be born will be called the Son of God” (Luke 1:35).
Matthew, chapter one, does record the genealogy of Joseph, from which one might easily assume that Matthew was relating the ancestry of Jesus’ descent from the lineage of David through Joseph. However, Matthew does not say this. He says only, at the end of the genealogy of Joseph, “And Jacob begat Joseph the husband of Mary, of whom was born Jesus, who is called Christ” (Matt. 1:16). Matthew carefully states that this genealogy is of “Joseph the husband of Mary, of whom was born Jesus.” Notice that Matthew identifies Joseph as “the husband of Mary,” not the father of Jesus. Luke also confirms this fact by saying that Jesus was “(as was supposed) the son of Joseph” (Luke 3:23), after which he recounts the lineage of Mary.
If Matthew truly recognized that Jesus was the Son of God, as he stated, and not of Joseph, what was his purpose in recounting Joseph’s lineage? He did it because Jesus was considered to be legally the son of Joseph, because of the wedlock of Joseph and Mary. But Matthew is very clear in explaining that Jesus was not biologically or physically the son of Joseph, even though this was commonly assumed.
Luke 3:23-38 records the genealogy of Mary, through her father Heli (thereby Joseph’s father-in-law) all the way back to Abraham and to Adam. (Joseph’s own father was Jacob, not Heli–see Matt. 1:16). Although both Joseph and Mary were of the lineage of Abraham, Jesus’ being of the tribe of Judah and of the family of David was through his mother Mary, not through Joseph. Mary’s line of descent came through Nathan, the son of David by Bathsheba (1 Chron 3:5).
Jesus’ being of the lineage of David was a fulfillment of prophecy. “There shall come forth a rod out of the stem of Jesse, and a Branch shall grow out of his roots” (Isa 11:1). Again, “ ‘Behold, the days are coming,’ says the Lord, ‘That I will raise to David a Branch of righteousness; A King shall reign and prosper…’ “(Jer 23:5).
The fact that Jesus was truly the Son of God is confirmed many times in the Gospels (see Luke 1:35; 4:41; 11:27; John 10:36; 20:31). The Apostles also confirmed this fact (see Acts 8:37; 9:20; Rom. 1: 4; Gal. 2:20; 1 John 5:5, etc.).