MARY, THE MOTHER OF GOD
Mary as Mother of God
Mary's most important title, "Mother of God," is another one of those things that are not clearly written in Holy Scripture. It was obvious, though, that she was the Mother of Jesus, because she gave birth to Him. But Mother of God? That was not a title that would usually be given to a woman, unless it is known for certain that the son of the woman was God.
However, the Bible was not completely silent about the fact that Mary was the Mother of God. This fact was hinted in Elizabeth's remark: " And whence is this to me, that the mother of my Lord should come to me?" (Luke 1:43) Besides this, however, all other hints from Holy Scripture were given indirectly, that is, by saying that Christ was God and that, by inference, His mother must be the Mother of God.
That Mary was the Mother of God is an article of faith because the divinity of Jesus, her son, is an article of faith. Doubt in the divinity of Christ leads to doubt in Mary's Motherhood of God. Therefore, the veneration of Mary as Mother of God is closely tied to the worship of Christ as true God and true man. A lot depends on one's Christology, or on how one views the Person of Christ.
In the early years of Christianity the Divinity of Christ was challenged by the Arian heresy. According to the Arians there was only one God. That was God the Father. They assumed that Christ was only a creature who was created before the world began, but by whom everything else was made. In short, Christ stood midway between the Father and the rest of the created world. However, Christ was not eternal like the Father is. He did not always exist. But he was described as a lesser "god" because, although he himself was created out of nothing, he made everything else.
In addition to the Arian heresy, there was another one - the Nestorian heresy - which made a more direct attack on Mary's title. Unlike the Arians, the Nestorian heretics did not deny the divinity of Christ. But they rejected Mary's title, theotokos ("God-bearer"), because, according to them, Mary was not the source of Christ's divinity, but only of His humanity. Nestorius (A.D. 386 - 451) was actually a well-meaning Bishop of Constantinople. He wanted to defend both the divinity and the humanity of Christ, but for lack of a clear distinction between "person" and "nature," he spoke vaguely as if there were two persons in Christ.
The difficulty of the heretics who denied Christ's divinity and those who rejected Mary's title was closely related to the difficulty of the heretics who denied the Blessed Trinity. It was rooted in the lack of clear distinction between "person" and "nature." But today, thanks to the work of the medieval theologians, it is possible to clarify the issues and avoid the difficulties that the early heretics struggled with:
Our Catholic Faith tells us that the Second Person of the Blessed Trinity took human nature and was born of the Virgin Mary. This is called the mystery of the Incarnation. In the mystery of the Blessed Trinity we see a plurality of distinct Persons united in one Divine Substance or Nature. In the mystery of the Incarnation we see a plurality of natures (human and divine) united in one Person, which was Jesus Christ, the Second Person of the Blessed Trinity.
Christ is only one substance, one suppositum, or one Person, but with two natures - human and divine. By his divine nature Christ is a doer of divine acts. By his human nature, he was also a doer of human acts. His substance (or Person) is both human and divine. It is human by the human nature that He has, and divine by the divine nature that He has or is. Christ is, therefore, both true God and true man.
Actions are acts of the Person, not of the nature. Although Christ had a human nature, the acts He performed by that nature still belonged to Him, as a Person. It was Christ, not his human nature, who was born of the Virgin Mary, and who suffered and died on the Cross. Since Christ was God, then it is completely accurate to say that a Divine Person suffered and died on the cross, but not as if He, as God, lost His eternal Life and Power. For it was only by His human nature that He died, and it was only His human life that He lost. Thus, says St. Thomas, "Christ is the fountain of life, as God, and not as man: but He died as man, and not as God... Accordingly, He experienced death by sharing in our human feeling, which of His own accord He had taken upon Himself, but He did not lose the power of His Nature, through which He gives life to all things" (Summa Theologiae, Part III, Q. 50, art. 1, Reply to Obj. 1).
It is because the Person who died on the cross was divine that Christ was able to atone for the sins of all mankind. Being divine, His passion and sufferings had an infinite merit, enough to cover the infinite malice of man's sins.
This is why it is also correct to speak of Mary as the Mother of God, because Mary is the mother of the Person, Christ, not the mother of the Child's human nature. Christ was God; therefore, Mary was the Mother of God. That the Child did not receive His divinity from Mary is not a valid objection to Mary's title as Mother of God. We, too, do not receive everything from our mother. For example, we do not receive our souls from our mother, because souls are directly created by God during conception. A woman is called the mother of a person, not because the person received everything from her, but because the person was born of her.
The Birth of Christ
From the Brooklyn Museum (1886-1894)
Image source link: marysrosaries.com
The Catechism of the Catholic Church, # 456-483, and Mother of the Redeemer (by Pope St. John Paul II) are recommended readings on this subject.
The Fathers Speak
During the years that faith in the divinity of Christ was being challenged, faith in Mary's Motherhood of God continued, thanks to Sacred Tradition. Below are some quotes from the Fathers of the Church and the Council of Ephesus attesting this fact.
St. Irenaeus of Lyons (A.D. 125-200), Against Heresies, Book V, Ch. 19, Par. 1: "For just as the former [Eve] was led astray by the word of an angel, so that she fled from God when she had transgressed His word; so did the latter [Mary], by an angelic communication, receive the glad tidings that she should sustain (portaret) God, being obedient to His word." (Names inside brackets were added for clarity.) Note: The Latin word portaret is more clearly translated "bear" or "carry," rather than "sustain." So, the phrase is better translated as, "she should bear God." This is an early instance of Theotokos (God-bearer) being applied to Mary.
St. Gregory Thaumaturgus (A.D. 213 - 270), Four Homilies, Homily #1, par. 2: "For Luke, in the inspired Gospel narratives, delivers a testimony not to Joseph only, but also to Mary the mother of God, and gives this account with reference to the very family and house of David..." (Italics added)
St. Methodius of Olympus (d. A.D. 311), Oration on Simeon and Anna, XIV: "Hail to you for ever, you virgin mother of God, our unceasing joy, for unto you do I again return. ... O holy mother of God, remember us, I say, who make our boast in you, and who in hymns august celebrate the memory, which will ever live, and never fade away." (Italics added)
St. Alexander of Alexandria (A.D. 250 - 328), Epistles on Arianism and the Deposition of Arius, Letter #1 To Alexander, Bishop of the City of Constantinople, par. 12, last sentence: "After this we know of the resurrection of the dead, the first-fruits of which was our Lord Jesus Christ, who in very deed, and not in appearance merely, carried a body, of Mary Mother of God, who in the end of the world came to the human race to put away sin, was crucified and died, and yet did He not thus perceive any detriment to His divinity, being raised from the dead, taken up into heaven, seated at the right hand of majesty."
General Council of Ephesus (A.D. 431), Formula of Union between Cyrill and John of Antioch: "We confess, then, our lord Jesus Christ, the only begotten Son of God perfect God and perfect man of a rational soul and a body, begotten before all ages from the Father in his godhead, the same in the last days, for us and for our salvation, born of Mary the virgin, according to his humanity, one and the same consubstantial with the Father in godhead and consubstantial with us in humanity, for a union of two natures took place. Therefore we confess one Christ, one Son, one Lord. According to this understanding of the unconfused union, we confess the holy virgin to be the mother of God because God the Word took flesh and became man and from his very conception united to himself the temple he took from her." (Italics added)