The New Testament does not often use the term ‘mediator’. One also looks for it in vain in the Apostolic Fathers and the Apologists. Jesus Christ does not stand between God and his people, nor is he God’s representative, as an angel could be, but he is himself ‘the author of eternal salvation’ (Hebrews 5:9). We do not wish to diminish the value of Christ’s mediation, quite the contrary. We realize, however, that such a doctrine differs from ancient teaching in two respects:
1. In the philosophical systems it was God who, because of his absolute transcendence, needed a mediator to communicate with the world. By contrast in Scripture such communication is made possible only by virtue of God’s condescension. Jesus stands explicitly on the side of God. It is God himself who performs the work of salvation through the man Jesus Christ, his Son.
2.This salvation could become effective only by means of a complete taking on by God of the human condition. The axiom ‘What is not assumed cannot be saved,’ which underlines the development in Irenaeus, is already found explicitly in Origen: ‘The whole man would not have been saved unless he had taken upon him the whole man.’ The union between the human and the divine is a ‘mixture’, a ‘blending’, but of a special type: indeed, the two natures remain unconfused. Christ is the only one to bring about the encounter of the divine transcendence with the hu-man finite, without sacri-ficing the one or ignoring the other. Jesus belongs au-thentically to the two orders of existence, that of God and that of man. ‘God and man have become one.’ The mystery of mediation is therefore the mystery of union, realized by the Son who is ‘one’ with the Father.
The Church struggled for years to come to a clearer understanding of the mystery of God’s Incarnation. In most ways His incarnation is beyond human comprehension. All we can say is that Jesus is truly God and truly man.