What we say about Jesus, when we call Mary the "Mother of God"

January 1^st, Solemnity of Mary the Mother of God

The doctrines of Mary which the Church believes, teaches, and professes are, in truth, doctrines about Christ. When the Church says “Mary” she is directing us always to Jesus.

Nowhere is this clearer than in the central teaching about our Lady – that she is truly the Mother of God. By insisting that our Lady is not merely the Mother of the Christ, but truly the Mother of God, the Church condemns two heresies concerning the Savior.

The Angelic Thomas speaks

“The Blessed Virgin is truly called the Mother of God. For the only way in which it could be denied that the Blessed Virgin is the Mother of God would be either if the humanity were first subject to conception and birth, before this man were the Son of God, as Photinus said; or if the humanity were not assumed unto unity of the Person or hypostasis of the Word of God, as Nestorius maintained. But both of these are erroneous. Therefore it is heretical to deny that the Blessed Virgin is the Mother of God.”

 - Summa Theologica III, q.35, a.4

Against Adoptionism

Against those who would claim that the Child conceived  in Mary’s womb were not truly God, but that he would only become God at a later time, the Church teaches that Mary is not merely the mother of the Messiah or the mother of one who would become God, but truly the Mother of God himself.

In this, we see condemned every heresy which would claim that our Savior was somehow not fully God from his conception. Those who say that he did not know all things, or that he was imperfect or could be tempted interiorly by sin, or that he was somehow only adopted as the son of God later – all these are condemned.

For, if Mary is called the Mother of God, then this must mean that the Christ Child is truly God. And, if he is God, then he surely knows all things (we speak only of his divine knowledge here, though we could also assert that he knows all things as man likewise), and he surely cannot sin or be interiorly tempted by sin (since God cannot suffer concupiscence).

Thus, those who claim that Jesus came to perfection only in his baptism, or after his resurrection, are sorely mistaken – for he is God from the beginning.

Whenever we ask the question: “Did Jesus know such and such?” We must remember that this “Jesus” of whom we speak is no mere man, but the true God. Thus, the answer is surely “Yes”. For, as God, he most certainly knew and knows all things absolutely.

Nor can any claim that this divinity was “limited” or “set aside” when our Lord came to earth – for it is the true God of whom Mary is Mother, and God cannot be limited.

Against Nestorianism

On the other hand, some will speak as though our Savior “left his divinity” with the Father. These persons suppose that it was a man who walked on earth, while the divinity remained in heaven.

However, if Mary is the Mother not merely of the Christ, but even of God, we know that the person to whom Mary gave birth must indeed be God himself.  As there is only one “Jesus” and only one “Son of God”, so too we must insist that the Child born of Mary is truly and wholly God.

Because Mary is Mother of God, the Jesus of Nazareth who walked upon the earth must truly be God himself. In this respect, any who would seek to divide the humanity and the divinity of Christ in such a way as to make his humanity a separate person or a separate subject from his divinity (as though we could mentally consider only the human nature apart from the divine person) are confounded by the dogma that Mary is the true Mother of God.

Thus, the foundational Marian doctrine serves to place our Lady as the great mediatrix who directs us always to her Divine Son.

Mary, Mother of God, Pray for us!