Christology 101 (Part 5): The Glory and Wonder of the Hypostatic Union

Dr. McKay Caston
3 min readNov 7, 2023

Historic statements of faith, such as the Apostles’ Creed, affirm the angels’ message to Joseph in Matthew 1, saying Jesus was “conceived by the Holy Spirit.”

This is to say, Jesus’ birth was utterly unique among all human births.

In theology, we call this the Hypostatic Union, a fancy theological concept that simply means Jesus is both fully God and fully human in one person.

The term hypostatic comes from the Greek hypostasis (ὑπόστασις, hupóstasis) which, in this context, can be understood as “substance” or “underlying reality.”

The Council of Chalcedon in 451 AD provided a definition of the hypostatic union, stating that Jesus possesses two natures without confusion, without change, without division, and without separation.

The distinction of natures was not nullified by the union between the divine and human, but rather the characteristics of each nature were preserved and came together to form one person.

Each nature retains its own properties without transferring the attributes of one to the other.

This is not to suggest the divine and human natures are united in such a way that they create a split personality. Rather, his human experiences, limitations, emotions, and physicality were genuinely his, just as much as his divine attributes like omniscience, omnipotence, and eternality.

Yes, there is mystery here. Such is often the case for finite creatures when contemplating the infinite.

What we can say to simplify matters is that, as the eternally pre-existent God,

  1. Jesus didn’t come into existence at his birth, and
  2. that in becoming human, Jesus did not cease to be God.

As the God–man with a sinless divine nature and a sinless human nature, Jesus is the one uniquely qualified to be our sin-substitute!



Dr. McKay Caston

I create resources to help folks tether their lives to the cross of the risen and reigning Jesus |