Summary
Christology is the careful study of the two natures of Christ—how Jesus is at the same time fully God and fully man. This is no abstract puzzle; it stands at the very center of the gospel. As Paul writes, "in Christ God was reconciling the world to himself" 2 Corinthians 5:19. If Jesus were not truly man, He could not stand in our place; if He were not truly God, His sacrifice could not avail for the sins of the world. Luther rightly said that "the entire gospel which we preach is based on this," and that this article of faith is "so rich and comprehensive that we never can learn it fully."
The Creeds as a Faithful Guide
The Lutheran Church confesses three ecumenical creeds—the Apostles', Nicene, and Athanasian—each developed for a particular reason. The Apostles' Creed grew out of the apostolic teaching Acts 2:42 and was used to prepare catechumens for baptism. The Nicene Creed (325, completed 381) answered the heresy of Arius, who denied the deity of Christ; the whole controversy hinged on a single Greek letter—homoousios (same substance) versus homoiousios (similar substance)—and the Church confessed that the Son is of the same substance as the Father, "begotten, not made." The Athanasian Creed dives deeply into the Trinity and the union of Christ's two natures: "existing fully as God, and fully as man." These creeds are not Scripture, but every line is drawn from Scripture, and they remain a faithful tool whenever a believer drifts from biblical truth. See Christology- Lesson 1 for the historical development of these confessions.
Why Christ Had to Be Truly Man
After the fall, a vast chasm opened between Creator and creature. Adam and Eve were driven from Eden under the sentence "you are dust, and to dust you shall return," and humanity now stands under the appointment "to die once, and after that the judgment." The Levitical sacrificial system pointed toward the remedy—an unblemished victim offered in the place of sinners—but those sacrifices had to be repeated continually, because no animal and no fallen human could be the final atonement. Only a sinless human could offer the once-for-all sacrifice Hebrews 7:26-28.
This is precisely what Christ accomplished. He shared in flesh and blood "so that through death he might destroy the one who has the power of death, that is, the devil, and free those who all their lives were held in slavery by the fear of death" Hebrews 2:14-17. He was tested in every way as we are, "yet without sin" Hebrews 4:15. Sin is not essential to humanity—it is a corruption of it. Jesus differs from us in only two ways concerning His humanity: He never sinned, and His body never decayed in death Acts 2:31. Christology- Lesson 3 traces the abundant scriptural and even secular witness to His true humanity.
Why Christ Had to Be Truly God
Christ also had to be truly God, because only divine power could bear the infinite weight of God's wrath against sin and offer a sacrifice of infinite value. No mere man could accomplish this. As 1 Timothy 2:5-6 confesses, "There is one God; there is also one mediator between God and humankind, Christ Jesus, himself human, who gave himself a ransom for all." In the incarnation Christ never set aside His divinity; He humbled Himself, choosing not to make full use of His divine power as He lived in obedience to the Father Philippians 2:5-8. Yet His glory still shone forth—at His baptism, at the Transfiguration, and as the eternal Word who created and sustains all things and is "the reflection of God's glory and the exact imprint of God's very being" Hebrews 1:1-4.
One Person, Two Natures, Inseparable
When we ask who suffered, who died, who rose—the answer is always: true God and true man, never separated. This is no plan B; before the foundation of the world God chose us in Christ and destined us for adoption Ephesians 1:4-10. Both natures act together to accomplish our salvation. As Christology- Lesson 5 emphasizes, this confession was revealed by the Father in heaven when Peter declared, "You are the Messiah, the Son of the living God" Matthew 16:13-17, and it is grasped by faith, not unraveled by reason.
Pastoral Comfort
The Formula of Concord wisely warns believers not to "arrogantly indulge their reason in crafty investigations" of these mysteries, but to bring our understanding into captivity to Christ and rejoice that "our flesh and blood is placed so high at the right hand of God's majesty." When two truths in Scripture exceed our reason—fully God, fully man—we can humbly say, "Lord, I don't fully grasp it, but you said it; therefore it is true."
Take comfort in this: because Christ took on flesh, you have a high priest who sympathizes with your weaknesses. Because He is divine, His sacrifice was sufficient for every sin. The fear of death no longer holds power over you, and you have been adopted as a redeemed child of the one true God. Jesus has never been anything other than fully man and fully God—before His incarnation, during His earthly ministry, and forever after His ascension. On this our salvation rests.
Video citations
- Christology- Lesson 1 — So today we are starting our study on Christ's Dology, which is figuring out how the two natures of Christ work and why both Jesus as truly man and truly God, 100% man, 100% God, why that's true and…
- Christology- Lesson 5 — Lord, we thank you so much. We thank you for this time to come together and dive further into your word, further into what Scripture has to say about you. We ask that you would bless this time of…
- Christology- Lesson 3 — Heavenly Lord, we thank You so much for this morning, for calling us into gather, to hear Your Word, and to receive Your sacrament. We ask that during this education hour that Your Spirit would…