“Then said Mary unto the angel, How shall this be, seeing I know not a man? And the angel answered and said unto her, The Holy Ghost shall come upon thee, and the power of the Highest shall overshadow thee: therefore also that holy thing which shall be born of thee shall be called the Son of God.” (Luke 1:34-35)
At the very beginning of the Christmas story the critical presence of the Holy Spirit is established. By Him, was the child conceived within the virgin Mary. He was not born of the seed of a man, but of the Spirit of God.
Even at the beginning of Genesis, when God promised that Christ would come, He spoke of “the seed” of the woman (Genesis 3:15). It was not the seed of a man that would be the source of the Son of God made flesh; it would be the Holy Spirit using the woman’s body to bring forth the Holy One of God.
In this way, Christ would not have the sinful nature of Adam handed down through the seed of Adam. Which all other men, born of the union between a man and a woman, possess. This would be a unique man — the Son of Man. The same One who, along with the Spirit of God, created all things that are made.