Advent: The Hypostatic Union & Christmas


So, you clicked on an article entitled “The Hypostatic Union and Christmas.” Pat yourself on the back, people like you are rare indeed.

What is “the hypostatic union” and why does it matter for Christmas?

Well, in short, the “hypostatic union” is the belief that the Son of God, Jesus Christ, was one person with two natures: a fully human nature and a fully divine nature. When we say that Jesus Christ was fully God and fully man, we are standing on the doctrine of the “hypostatic union.”

In the incarnation, the Christmas climax to say the least, we have the Son of God enter into the world by taking on a human nature enfleshed. When the Son of God assumed this human nature, he did not surrender his divine nature or rights. While he did descend from heaven, surrendering for a time the glories of heavenly splendor to walk the paths of a broken world, he did not surrender his divine nature and stop being God the Son.

This issue, the issue of who Jesus Christ was, was the key theological issue of the first four hundred years of the church’s life. The clearest expressions are the Council of Nicaea and the Council of Chalcedon, both of these meetings of church leaders were organized to seek clarity and consensus on what the church believed concerning the person of Jesus Christ.

Historically there are five big misunderstandings (heresies) of who Jesus Christ was:

  • Arianism: The Son is not of the same substance as the Father.

    • Bottom line: The Son is like God, but not God.

  • Docetism: The humanity and sufferings of the earthly Christ are an appearance, they aren’t real.

    • Bottom line: Jesus Christ wasn’t really fully human, He just appeared to be.

  • Apollinarianism: The Son of God assumes human body, but not a human soul/spirit.

    • Bottom line: God isn’t really fully human, because humans are not just bodies, but both body and soul.

  • Nestorianism: The Son of God is fully God and fully man, but they are two different things…separated.

    • Bottom line: Denies two natures, one person, makes the Son of God something other than a person.

  • Eutychianism: The two natures (human and divine) mix together and become a third thing.

    • Bottom line: Mustard is good, chocolate is good. Mix them together and the creation is revolting.

Why does this matter for Christmas?

It’s really the whole point. The Son of God, second person of the Trinity, has entered the world in the form (human nature/flesh) of a human, beginning as a baby.

He is the image of the invisible God, the firstborn of all creation. For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things were created through him and for him. And he is before all things, and in him all things hold together. And he is the head of the body, the church. He is the beginning, the firstborn from the dead, that in everything he might be preeminent. For in him all the fullness of God was pleased to dwell,and through him to reconcile to himself all things, whether on earth or in heaven, making peace by the blood of his cross.
— Colossians 1:15-20 (ESV)

At the same time that the Son of God, Jesus Christ, was growing in Mary’s womb He was holding the world together (Co. 1:15-20). This is the mystery and truth of the hypostatic union.

As Calvin said, "The son of God descended from heaven in such a way that, without leaving heaven, he willed to be born in the virgin’s womb, to go about the earth, and to hang upon the cross; yet he continuously filled the world even as he had done from the beginning!”

Kyle Worley