Echoing Luther's theologic, (and also Athanasius and Anselm's), Chrytraeus writes:
"Why was it necessary that there be a unity between the two natures, divine and human, in Christ our Mediator? . . . First, it was necessary that He be a man because man had sinned and the course of justice would demand that he pay the penalty. He had to be a man to be able to suffer and die on behalf of man. Again that was necessary in order for Him to show His love for people to people with the assumption of human nature, and to glorify that love for people (which the devil had terribly torn apart and crushed) by His being taken up and placed at the right hand of God the Father. Second, he had to be God to provide a ransom or payment for sins and to be a merit sufficient for new righteousness and life. He had to be God to be able to sustain the burden of the wrath of God and its punishments, to overcome death and the devil, and to restore righteousness and life. Again, He had to be God in order to enter into the Holy of Holies, to look into the heart of the Father, to be present to the hearts of those who call upon Him and everywhere in the Church, to listen to those who call upon Him and defend and preserve them, and to give the wisdom of God and His Holy Spirit to those who ask for such gifts. Because at the first creation the Logos, the Son of God, had given to people the life and light which was the image of God; it was fitting for divine wisdom that the image of God which had been corrupted be restored in us with the same Word with which it had been created."