The World's First Love by Archbishop Fulton J. Sheen. Part 17.

As Father Joseph Tennant points out, there is a type of this miraculous birth in the story of Abraham and Sara. When they journeyed down to Egypt, Abraham asked Sara to say that she was his sister, rather than his wife, lest the Egyptians kill him. The Pharaoh took her into his household. How long she lived with the Egyptian king is not indicated, but some space of time, and the Pharaoh and his household were punished with a sickness because of it. He finally dismissed both Abraham and Sara from his palace. There is no expression of divine wrath reported in this case. But after God had promised that Sara would bear a son whose father would be Abraham, it was important that there be no doubt in Abraham's mind or in anybody else's about the paternity of Sara's son. Some time after the promise, in Gerara, there was danger that the king, Abimelech, would take her into his harem. With shameful cowardice Abraham permitted it to be done. (He was punished for this when God ordered him to sacrifice Isaac.) But God intervened immediately by appearing to Abimelech at night and threatening to wipe out his whole kingdom if he dared to touch Sara. "And Abimelech forthwith rising up in the night... called for Abraham and said to him, 'What hast thou done to us?'" It was not enough merely to have protected Sara. Abraham had to know from the lips of Abimelech himself that Sara was untouched, just as Joseph did in the case of Mary. And thus Isaac, the first of the "children of promise" (Gal. 4:28) and of the miraculous seed of Abraham, was born.

Mary was not sinless because she was a virgin, but the best sign of her sinlessness was her virginity. Just as the Gospels prove the humble humanity of Christ by naming among his ancestors Lamech, the boastful murderer, Abraham, the coward, Jacob, the liar, Judas, the adulterer, Ruth, the pagan, David, the murderer and adulterer, and many idolatrous kings, showing that He was like to us in all things except sin, so, too, the same gospels disassociate Mary from all sin in order to show her to be as much as possible, "in the image and likeness of God." Mary was of the house of David, but Christ's relationship to that line is not given through Mary, but through Joseph, His foster father. And it had to be that the Mother of God was sinless in order that we might more easily believe that she had flung before the face of the world woman's greatest challenge to sin - the vow of virginity -and kept it and made it bear divine fruit.

We do not believe that Jesus is God because He was born of a Virgin Mother, as the Apostles and Evangelists did not believe it for that reason alone. We believe in the Divinity of Christ because of the evidence of the Resurrection, the marvel of the Gospel portrait, the growth of the Church, the miracles and prophecies of Christ, the consonance of His doctrine with the aspirations of the human heart. The Virgin Birth is rather related to the manhood of Christ, and His separateness from the sin that affected all men who are born of the union of man and woman. Far from treating the Virgin Birth as the dazzling mark of Divinity, the Te Deum regards it as Our Lord's sublime condescension to the lowly conditions of humanity:

When thou tookest upon Thee to deliver man: Thou didst not abhor the Virgin's womb.

The Virgin Birth is the safeguard of the sinlessness of the human nature which Our Blessed Lord assumed. The only salvation that is given to men on this earth is in the Name of Him Who as God Himself entered the ranks of sinful men. That no one should ever deny He was a man. He was born like the rest of men from the womb of a Woman - a fact that so scandalized Marcion that he said: "A babe wrapped in swaddling clothes is not the kind of a God that I will adore."

In the Incarnation, God the Son initiates the process of the re-creation of His own earlier and disordered creation by the method of clothing Himself with those very elements within it which had fallen into disarray. For the first time since the Fall of Man, a completely perfected unit of humanity is created in the world. This humanity is united substantially to the very Person of the Son of God.

What do all denials of the Virgin Birth testify? Generally, to the subtle attempt to pull down the new order of humanity and the race of the second Adam into the unredeemed world of the old Adam. If a human father supplied the human nature of Christ, then Christ is not the new Adam. The Virgin Birth keeps the Divine initiative of Redemption to God Himself. If the initiation of the new order is given to man, then it is taken from God. Without the Virgin Birth Our Lord would be entangled in a sinful humanity. With it He is Incarnate in humanity without its sin. By getting rid of the  Virgin Birth one seeks to get rid of the Divine Initiative within the race of the new Adam. The early heretics doubted the humanity of Our Lord, and so they denied that He had a human mother. Modern agnostics doubt the true Divinity, so they add a human father to His parentage.