Christmas Is the Greatest Mystery

It is the hour that split history in half.

Until that first Christmas, he had been, from eternity past, the divine Son and second person of the Godhead. He was God’s glad agent in creation (John 1:3; Colossians 1:16; Hebrews 1:2), and from the beginning of time, he had upheld the universe at every moment (Colossians 1:17; Hebrews 1:3).

But then came the great change — the blessed addition — at the very heart of reality. The Word became flesh (John 1:14). God became man. The Creator himself came as a creature, the Author entered into his Story as a character. Without abandoning any of what it means to be God, he took on all that it means to be human.

“Without abandoning any of what it means to be God, he took on all that it means to be human.” #incarnation

This spectacular truth, at the center of what we celebrate at Christmas, we call “the incarnation,” which means the “in-fleshing” of the divine Son — God himself taking human flesh and blood and all our humanness. Christmas is when he adds humanity to his divinity, and does so that he might rescue us from our soul-destroying rebellion, and lavish us with the everlasting enjoyment for which we were made.

That Enigmatic Union

It is a glorious revelation, and it’s also a great mystery. This is the greatest mystery in all of history, how God himself became fully human without ceasing to be fully divine — that God, in all his God-ness, united himself with all man-ness. Church history has coined it “the hypostatic union,” the joining of two distinct natures in one undivided person (“hypostatic” is just a fancy word for “personal”). Jesus is fully God and fully man in one spectacular person.

And this union of God and man in Jesus is what makes possible our own union with the Godhead through him. But the greatest mystery is not how we are united to God by faith (through sheer grace and the work of the Spirit), but how God united himself to us in the one person of Christ.

“The union is so perfect,” says D.A. Carson, “that even though he has two natures, he is only one person.” It is almost too good to be true.

And so, “Jesus really does shoulder with us everything that it means to be human,” adds Russell Moore.

He Really Is Human

When you ask Moore about the person of Christ, it’s Hebrews 2:11–14, about Jesus’s humanness, that springs to mind.

“The humanity of Jesus is often the difficult thing to understand for evangelicals,” he says. We’re quick to embrace Christ’s deity, at least the orthodox among us. We’ve learned from day one that Jesus is God. “We understand his deity. But also, he was a real and genuine man, and is a real and genuine man.”

Moore rehearses “four fences” that come from the early church councils and guard us from error when it comes to this great Christmas mystery in the person of Christ: He is 1) fully God, 2) fully man, 3) as one person in 4) two natures.

He “Emptied” Himself

One difficulty in this for the human mind is that we’re prone to think of divinity and human in mutually exclusive terms. We might speculate, If he “became man,” he must have ceased, in some sense, to be God. Then we come across a text like Philippians 2:7, that he “emptied himself,” and ask, Did he empty himself of attributes of deity? Carson answers,

The expression is not what he emptied himself of; it’s an idiomatic way of saying he became a nobody, he humbled himself completely, not only to become a human being, but to go all the way to the ignominy and shame and torture of the cross. . . . It’s talking about the astonishing, unequal, unimaginable, indescribable, self-humiliation in becoming human and then going so far not only to be a slave, but a slave who dies on the cross.

The Mystery That Reveals: Three Lessons

The incarnation remains a great mystery, but Scripture does not leave everything enigmatic. From our 17-minute interview with Carson and 14 minutes with Moore, here are three important lessons this otherwise mysterious doctrine reveals.

1. Divinity and humanity are not mutually exclusive.

“The two natures do not diminish each other,” says Carson. “He is genuinely human, with all that means, and genuinely God, with all that means, in two natures that maintain distinctness, even while, at the same time, we insist that they are so united that he is but one person. . . . It’s language like that that is needed to preserve all the different contributing voices of the New Testament to explain adequately, in summary form, what the Bible says about Jesus as the God-man.”

And this lesson in the person of Christ, that full divinity and full humanity are complementary, provides a glimpse into other mind-bending, multi-dimensional realities as well, like the divine-human authorship of Scripture, and the divine-human tension between the sovereignty of God and the responsibility of man.

2. Humanity matters, as do our menial lives.

Moore mentions Jesus’s three decades as “a working-class day-laborer in a completely-out-of-the-way place.” Year after year of his quiet life, before launching into “public ministry,” serves a remarkable affirmation and sanctification of our mundane and obscure lives.

And his becoming man also highlights the amazing value, privilege, and dignity of humanity as God’s climactic creatures. Even above angels. These “things that have now been announced to [us] through those who preached the good news” are “things into which angels long to look” (1 Peter 1:12). It is not an angel who now sits on the throne of the universe, but a man (Hebrews 2:9). What amazing grace that Jesus is “not ashamed to call us his brothers” (Hebrews 2:11).

3. Jesus is the linchpin of prayer and worship.

In becoming man, he became for us the visible image of the invisible God (Colossians 1:15). He is the radiance of his Father’s glory (Hebrews 1:3). Our “light of the knowledge of the glory of God” comes “in the face of Jesus Christ” (2 Corinthians 4:6), and he is the singular “lamp” who will give the light of the glory of God in a new creation with no need of sun or moon (Revelation 21:23).

And so, says Moore, praying “in Jesus’s name” is no magical incantation. “Jesus is the only human who has the right to approach God.” Who may ascend the hill of the Lord? is the question of Psalm 24, and the ultimate answer is that Jesus is the only one who utterly fulfills the vision, and only in him may we too ascend.

The greatest mystery of Christmas is also its greatest revelation. “God has joined himself with us forever,” says Moore. “God has identified eternally with us.”