Luther’s understanding of the Incarnation concerns various subject areas in his theology, among them his understanding of scripture, his teaching on the sacraments in particular, as well as his description of a human being’s life of faith. All these subject areas are based on Luther’s Christology, which is essentially determined by his insights into the Incarnation and the humanity of God in Jesus Christ.
Luther’s description of the Incarnation and the humanity of God is particularly oriented towards the creed of Chalcedon. The insight that Christ is at the same time true human and true god is something Luther holds as relevant to salvation. For this reason, it is important for him on the one hand to think about the Incarnation of God in a Trinitarian context and thereby to highlight Christ’s divine existence. On the other hand, he refers to the concept of the Virgin Birth in order to show that God was born a real human being. Luther describes the union of God and man in Christ principally as a reciprocal exchange of the respective divine and human characteristics. He uses the figure of the communication of properties (communicatio idiomatum) to highlight the Incarnation’s fundamental significance for salvation, which becomes manifest in the course of Christ’s life.
Luther’s conception of the fact and manner in which human and divine natures are united with each other in Christ is of soteriological relevance. With the incarnate God, the sin that Christ has taken upon himself for the salvation of humankind is defeated on the Cross, since by virtue of his human nature the characteristics of being able to suffer and to die were proper to the incarnate Son of God. Accordingly, God himself suffers and dies on the Cross in Christ for his own creatures under the burden of their sins. On the Cross, the God who died in Christ and with his resurrection has overcome the death of sin meets his creatures so that they attain faith and ultimately eternal life in community with God. This saving event is, according to Luther, founded in God’s immeasurable love.
The saving effectiveness of Incarnation, Cross, and resurrection presupposes Christian proclamation, according to Luther. The preaching of the incarnate God is needed, so that through the operation of the Holy Spirit the truth of the proclaimed event can be recognized and faith can thereby arise. In faith in the Son of God who has become man, the believer himself experiences a most intimate connection with Christ. According to Luther, this community of faith determines the consummation of the life of the believer, who therefore lives in love for God and for neighbor because the love of God has been revealed to him/her in Christ.
The community of Christ’s faithful with one another is, according to Luther, above all formed through the celebration of the sacraments. In celebrating them, the believers experience the real presence of the incarnate God in Christ, through whom they are bound in faith based on the communication of properties between the human and divine natures.
God’s Love in the Teaching of Cardinal Stefan Wyszyński