...Because Jesus did not have an immediate human father, he was not entailed in sin with the rest of us. Because he had a true human mother, he was as human as we are; because he was without sin, he was more fully human than we are. From this we can see that the virgin birth is not just a random miracle story, designed to impress the gullible. It is a miracle, all right, but it is a miracle like the other miracles connected with the person of Jesus Christ. Like the incarnation itself, this miracle is necessary for the salvation of lost and sinful men.
Jesus Christ was “descended from David according to the flesh and was declared to be the Son of God in power according to the Spirit of holiness by his resurrection from the dead” (Rom. 1:3–4). The Spirit who worked powerfully in that resurrection was the same Spirit who exercised his power when Mary first conceived. It was the same person, the same purpose and plan, and the very same power (Luke 1:35).