The gospel is not merely about Jesus Christ. Jesus Christ is the gospel. Solus Christus means that salvation comes to sinners “through Christ alone.” Salvation, to be sure, involves professing those doctrines we hold to be true, but it also involves receiving in our hearts the divine-human person, in whom are all the benefits of redemption.

Together with Scripture, grace, faith, and the glory of God, solus Christus is one of the so-called “five solas” of the Reformation. Reformed Christology, however, is generically catholic in that it drew from the classic Christian tradition. It is distinctively Reformed in relation to the application of the doctrine of Christ to believers.

Drawing from both the common and the distinctive aspects of Reformed Christology is vitally important for preserving and promoting the gospel of Jesus Christ in its purity and power. Only in doing so will Reformed churches be able to promote the doctrine of living to God, through Christ, by the Spirit. There remains a need for a catholic Christology in Reformed churches today, as well as a full-bodied Reformed view of the application of Christ’s work to us.

A Catholic Christology

In a sense, Roman Catholics and Protestants both confess that salvation is solus Christus. Although Roman Catholicism teaches that Christ does not give believers all of the merits that they need for salvation at once, its official dogma teaches that even the merit of saints and angels come to believers through Christ in some manner. This reflects the fact that Christ is uniquely the Savior, both in Roman Catholic and in Protestant theology. While the end results of these confessional teachings are strikingly different for Roman Catholics and Protestants, they draw from the same Christological tradition.

Protestants have recognized that Scripture alone is the only rule of faith and practice. However, our forefathers also recognized that theology is not written without context. The Reformers believed that it was impossible for their churches to retain a sound Christology without appealing to the historical reflections of the church in turn. The early church took several centuries to hammer out the basic vocabulary needed to describe who Jesus is. The apostle John countered those who denied his true humanity (1 John 4:1–2). Athanasius and others rejected the teaching of the Arians, who denied his full divinity.

Later theologians countered the teaching of Nestorius, who was accused of separating the divinity and humanity of Christ into two persons. This controversy in turn prompted reflection on Christ’s full divinity and genuine humanity being joined in one person.

By searching the Scriptures, the church concluded that Christ’s two natures were united in one person without being mixed or confused. Each nature retained its proper attributes, but Scripture often ascribes the works of either nature to the whole person.

The church also held, among other truths, that Christ has both a divine and a human will. By consistently refuting partial truths, the church gradually gained a clearer Christology from Scripture. It is hard to see how the church today could retain these mature reflections on the Savior by starting over in every generation.

In this light, it is not surprising that Reformed theologians interpreted Scripture in light of the ancient creeds. This is true of both the Reformation and the post-Reformation periods. While modeled loosely on the book of Romans, Calvin’s Institutes, for example, follows the ancient model of the Apostles’ Creed. Heinrich Bullinger’s Decades likewise opens with a treatment of the Creed and interprets it in light of Scripture and later creedal theology. Zacharias Ursinus incorporated the ancient creeds in his exposition of the Heidelberg Catechism.

In the early seventeenth century, Amandus Polanus began his treatment of theology proper by citing Christian creeds in full from the early church through the medieval period. When the Westminster divines designed a catechism for beginners in the faith, they too stated succinctly: “The only Redeemer of God’s elect is the Lord Jesus Christ, who, being the eternal Son of God, became man, and so was, and continueth to be, God and man in two distinct natures, and one person, forever” (WSC 21).

Solus Christus must begin with a catholic confession of Christ. We should be surprised (and grieved) if members of our churches can say little about who Jesus is. If we love Christ and rejoice in him “with joy unspeakable and full of glory” (1 Peter 1:8), then should we not seek to know him as well as we can? If the hope of seeing Christ as he is in glory motivates our faith and life on earth (1 John 3:1–2), then can we be content to say only that we know that he is our Savior? We need a catholic Christology that grows out of the labors of pastors and teachers from the past in order to avoid being tossed about by every Christological wind of doctrine and to come to a unity of the faith and to maturity in our Lord (Eph. 4:11–16).

A Reformed Christology

The primary contribution to Christology made by Protestant theology in general, and by Reformed theology in particular, lies in soteriology. This relates to many areas of faith and practice, but especially to Christ’s two natures and to the scope of salvation in Christ.

While the Reformed faith teaches that Christ is our Meditator in both natures (e.g., WLC 38–40), some medieval authors, such as Thomas Aquinas, taught that Christ is our Mediator in his human nature only. He held that while the divine nature informed all of the actions of the human nature, Christ is our Mediator in his human nature only, because he represents us only in his perfect humanity. While this view is close to the truth, Reformed authors have generally agreed that attributing Christ’s work only to his human nature threatens to divide the unity of his person.

In the mid-seventeenth century, Patrick Gillespie represented the mature Reformed consensus on this point. He argued in The Ark of the Covenant Opened, first, that Christ’s names and offices agreed with both natures. Second, his Godhead concurred with his humanity in every act of his mediation. Third, many  acts of his work depended on his divine nature. Fourth, as Mediator, he performed many divine acts in his earthly ministry. Fifth, none of his mediatorial acts occurred without the concurrence of the other nature. Sixth, the union of both natures in the incarnation was requisite for his work as Mediator.

Illustrating these points in relation to Christ’s death, Gillespie wrote, “It was the Son of Man, the Lord of life, that died on the cross, but it was the nature of man, not of God, wherein he died; yet it was the divine nature that did support him, and gave worth to his sacrifice.” This view, taken as a whole, presses us to rely on Christ’s entire person in both natures more fully than does its medieval predecessor.

Reformed theology also has a multifaceted view of how Christ alone saves us. Contrary to some Roman Catholic caricatures, which persist to the present day, Reformed theologians did not reduce salvation to forensic justification. Everything Christ did, he did for us and for our salvation. We must, however, be united to Christ by faith in order to receive any of these benefits. When we receive Christ by faith, his perfect obedience becomes our perfect obedience. His suffering under God’s wrath and curse frees us from the curse of the law. These elements constitute our justification in Christ, and they spill over into Christ’s vindication by the Father in his resurrection, becoming our vindication before God in Christ.

Because Christ is the natural Son of God, we become the adopted children of God (John 1:12; Gal. 4:1–7). Because Christ is raised, we are alive to God and sin no longer has dominion over us. Therefore, our bodies will rise in Christ at the resurrection. This is the ground of our sanctification. Since Christ ascended into heaven, he made a place for us (John 14:1–2), and he ever lives to intercede for us, so that we might be with him and behold his glory. Westminster Larger Catechism 65–90 describes the entire Christian life and every element of salvation in terms of union and communion with Christ in grace and in glory. This is why Christ “became for us wisdom from God—and righteousness and sanctification and redemption—that, as it is written, ‘He who glories, let him glory in the Lord’ ” (1 Cor. 1:30–31).

The ideas embedded in the confession of solus Christus are vital to biblical Christianity, shaping both our doctrine and our practice. If the Trinity is the foundation of all fundamental articles of the faith, then Christology invites us into the fellowship of the triune God. Yet we must remember that sound doctrine is a means of knowing God in Christ by the Spirit, and so the gospel is the ground of our personal experience as well. While the Spirit brings Christians to Christ in different ways, we all have the same testimony, which is the work of Christ. Confessing solus Christus means receiving and resting on Christ, the whole Christ, and nothing but the Christ, as he is offered freely to us in the gospel.

The author, an OP minister, teaches at Greenville Presbyterian Theological Seminary. He quotes the NKJV. New Horizons, October 2017.