Mary is the mother of God.
This statement might ruffle evangelicals’ feathers. For some, it suggests idolatry. Yet affirming Mary as the mother of God has nothing to do with Mary. It has everything to do with the nature of her son, Jesus. This ancient way of referring to Mary recognized Jesus truly was God in the flesh.
In the early fifth century, a controversy regarding the person and nature of Christ erupted between the patriarch of Constantinople, Nestorius, and the patriarch of Alexandria, Cyril. Nestorius refused to refer to Mary as the Theotokos, Greek for “God-bearer/mother of God.” Cyril responded with On the Unity of Christ, a classic account of orthodox Christology written as a dialogue between himself (“Speaker A”) and another Christian.
Looking at the two sides of this debate 15 centuries later can help us understand how the church has historically spoken of Christ.
Nestorian View
Nestorius believed calling Mary “the God-bearer” communicated too strong a union between the Word of the Father and the human Jesus Christ. In particular, it improperly attributed to the divine nature things like being born in time, changing, learning, and suffering loss (53, 107). Nestorius thought he was safeguarding orthodoxy, but Cyril recognized Nestorius had undermined the foundations of the faith.
Nestorius denied that the one person, Jesus Christ, was fully God and fully man. Instead, he promoted a looser, personal union between the person of the Word and the person of Jesus Christ. To Nestorius, Jesus related to the second person of the Trinity in the same way believers like Abraham did, but Jesus did so more completely than anyone ever had (68). Thus, in Nestorius’s system, the incarnation wasn’t unique in kind but in intensity. Jesus wasn’t truly God in flesh but merely a man who had a unique relationship with the Word (52). Nestorius, then, was willing to call Mary “mother of Christ” but not “mother of God.”
What’s at Stake?
Cyril recognized the stakes of Nestorius’s position. For him, the church would commit a grave error by denying Mary was the Theotokos. As he explained,
When they say that the Word of God did not become flesh, or rather did not undergo birth from a woman according to the flesh, they bankrupt the economy of salvation. . . . If the Word has not become flesh then neither has the dominion of death been overthrown, and in no way has sin been abolished, and we are still held captive in the transgressions of the first man, Adam, deprived of any return to a better condition; a return which I would say has been gained by Christ the Savior of us all. (60)
If Jesus wasn’t truly God in the flesh, then no reconciliation had been made between God and man.
If Jesus wasn’t truly God in the flesh, then no reconciliation had been made between God and man.
Just as important, Cyril believed Nestorius’s position simply lacked biblical evidence (51). Throughout On the Unity of Christ, Cyril appealed to a plethora of biblical texts to show Jesus, being fully human, was none other than the eternal Son of the Father (133). Among the passages he cited were:
Exodus 3
Psalms 22; 45:6–7
Matthew 22:42–45
John 1:1–18, 3:31, 17:5
1 Corinthians 15:49
Ephesians 4:5
Philippians 2:5–11
Colossians 1:15–20
Hebrews 1:1–5; 2:17; 12:1–2
1 John 4:1–2
These form a sample of the passages Cyril used to demonstrate the wonderful mystery that the child born of Mary was the eternal Word of the Father (109). Because Jesus is Emmanuel, or “God with us,” Mary is the mother of God.
Making Sense of the Gospel Accounts
One of the major passages Cyril used throughout his work was Philippians 2:5–11. According to Cyril’s interpretation, the Word emptied himself not by dispensing with any aspect of his divine nature but by taking on the limitations of humanity. In this assumption of human nature, Cyril clarified, nothing in Jesus’ divine nature underwent any change. Nor, he added, had Jesus inherited his divine nature from Mary nor made himself subordinate to the Father on account of the incarnation (86). Rather, as Cyril commented,
The Only-Begotten Word, even though he was God and born from God by nature, the “radiance of the glory, and the exact image of the being” of the one who begot him (Heb. 1:3), he it was who became man. He did not change himself into flesh; he did not endure any mixture or blending, or anything else of this kind. But he submitted himself to being emptied and “for the sake of the honor that was set before him he counted the shame as nothing” (Heb. 12:2) and he did not disdain the poverty of human nature. . . . He was God in an appearance like ours, and the Lord in the form of a slave. This is what we mean when we say that he became flesh, and for the same reasons we affirm that the holy virgin is the mother of God. (55)
This incomprehensible union of the two natures in one person framed Cyril’s entire conception of salvation (60). “In short,” Cyril claimed, “[Jesus] took what was ours and made it his very own so that we might have all that was his” (59).
How, then, did Cyril make sense of the obvious weaknesses the baby born to Mary endured? He simply appealed to the witness of the Gospels, which had no issue applying “all the divine and human characteristics” to Christ alone (68). Cyril acknowledged human weaknesses “would not be at all fitting to the Word, if we considered him nakedly, as it were, not made flesh,” but Jesus is the Word made flesh. One can, therefore, understand the weaknesses of Christ by virtue of his human nature. For example, with respect to the suffering of Christ, Cyril wrote,
Since he is God by nature, he is conceived of as beyond suffering, and then he chose to suffer so that he might save those under corruption, and so became like those on earth in all respects, and underwent birth from a woman according to the flesh. As I have said, he made his very own a body capable of tasting death and capable of coming back to life again, so that he himself might remain impassible and yet be said to suffer in his own flesh. In this way he saved what was lost (Matt. 18:11) and openly said: “I am the Good Shepherd. The Good Shepherd lays down his own life for the sake of the sheep.” (127).
Since Christ was fully human, he could suffer and die in our place; since he was God who is life itself (John 1:4), suffering no loss in himself, he could set us free from death’s bondage and take his life and make it ours.
Unity and the Beauty of the Gospel
On the Unity of Christ is as relevant today as it was when Cyril first wrote it. It helps us rightly understand the scriptural affirmation of Mary as the mother of God, grounding it in the conviction that Jesus Christ is God in the flesh.
More than anything, Cyril’s concern is the beauty of the gospel. Many religions hold up a particular human as the supreme example, but Cyril didn’t. He knew humanity needed healing only God himself could provide.
More than anything, Cyril’s concern is the beauty of the gospel
For the Scriptures make known this glorious mystery that the One who commands the sea in his infinite power grows tired. The One who knows all things learns. The One who has in himself the power to raise the dead died and rose again. For having become truly human, the incorruptible One was able to suffer and die in our place, the righteous for the unrighteous, so all who believe in him might be cleansed of their sins and enjoy eternal life with him. This gospel message is the heart of Cyril’s On the Unity of Christ, and it ought to be the heart of our daily walk with Christ as well.
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