Differences in Christology

Christology seeks to answer fundamental questions about Christ—who he was, what he was, and why he acted as he did—within the limits of human reason. While various answers have been proposed throughout history, the Church has worked to clarify and define these truths. During the Protestant Reformation, both Martin Luther and John Calvin advanced their own Christological perspectives, sometimes aligning with Catholic teaching, but often diverging from it.

A key theological concept in Christology is the communicatio idiomatum, or the "communication of properties." This doctrine expresses the way Christ’s two natures—divine and human—are united in the one divine Person of the Son. It means that, while the divine and human natures remain distinct, the properties of each nature can be attributed to the one Person of Christ. Thus, it is correct to say, for example, that "God suffered" or that "God was born of the Virgin Mary," because the Person who suffered and was born is truly God, even though suffering and being born are properties of his human nature. However, Catholic theology maintains that these properties do not transfer between the natures themselves—divinity does not become subject to suffering, nor does humanity become omnipotent. This nuanced distinction ensures a proper understanding of Christ’s identity and work in salvation.

Luther and Calvin both affirmed the union of Christ’s divine and human natures. However, Luther’s understanding of this union leaned toward a more fused relationship. He interpreted the communicatio idiomatum in a way that allowed attributes of one nature to be predicated of the other more freely than in Catholic theology. This led him to assert that Christ’s death had a direct effect on God, a position that differs from Catholic teaching. Additionally, Luther’s interpretation contributed to his belief in the real presence of Christ in the Eucharist, arguing that Christ’s human nature, through union with the divine, could be present in multiple places at once. In contrast, Catholic teaching maintains that Christ is truly present in the Eucharist through transubstantiation, but without his human nature taking on divine attributes such as omnipresence.

Both Reformers agreed that Christ bore the sins of the world and that divine justice required the outpouring of God’s wrath. According to their view, Christ redeems humanity by accepting this wrath and suffering the punishment due to sin, thereby securing the acquittal of sinners. His righteousness is then imputed to believers, covering their sins. Luther, in a paradoxical turn, suggested that in his human nature, Christ recoiled from this punishment, concealing his love for the Father beneath that fear. In contrast, St. Anselm articulated a different perspective: Christ offers himself as a willing sacrifice, atoning for sin through an act of perfect love and obedience. His voluntary self-gift, being of infinite value, restores humanity, making it truly righteous and sanctified. Furthermore, Catholic teaching, as developed by St. Thomas Aquinas, emphasizes that Christ’s Passion is not simply a punishment endured but a sacrificial act of love, renewing humanity’s participation in divine life.

In Luther’s theology, Christ and the Holy Spirit create a "new man" in the believer, whose faith naturally results in good works—though these works hold no merit for salvation. Calvin similarly taught that Christ’s resurrection brings new life to believers, but while righteousness remains merely imputed, the Holy Spirit sanctifies the elect within the Church, uniting them to Christ. Catholic teaching, however, affirms that believers are not only declared righteous but truly become righteous, as both the individual and the Church are sanctified through Christ. The Council of Trent explicitly rejects the idea of mere imputation, teaching instead that righteousness is infused into the believer through grace, transforming them interiorly (Trent, Session VI, Canon 10). This transformation is integral to the doctrine of divinization (theosis), which holds that salvation is not merely about legal justification but about participation in the divine life itself.

While Luther and Calvin retained some elements of Catholic Christology, their soteriology significantly diverged, particularly in understanding Christ’s mission and its role in salvation. Rather than revealing a merciful Father, their theology seems to present a divine economy in which God punishes the innocent and acquits the guilty—a framework that raises concerns about divine justice appearing arbitrary. In contrast, Catholic teaching emphasizes that the Second Person of the Trinity freely offers himself as a gift for all humanity out of pure love. This self-giving love not only redeems but also restores humanity’s capacity to love God in return and enter into a true relationship with Him. Through this relationship, humanity is drawn into the very life of God, fulfilling the ultimate purpose of the Incarnation.