Only a man? What would that mean?

But if Jesus is only a man, then His death on the Cross, and indeed His whole life, has no reconciling significance, and “we are yet in our sins”. If Jesus is only a man, then His word of forgiveness has no value for us. No <>man<> can know whether God forgives. Either Jesus could say this in virtue of a prophetic revelation, or He could say it because He Himself knew it, because He Himself came to us out of the mystery of the Father. Jesus’ whole life, which is fulfilled in His Passion and Death and does not merely <>end<> there, is full of the authority of Him, who, in the very authority and power of God, not only proclaimed reconciliation but accomplished it, and His resurrection, moreover, revealed His divine power of reconciliation. To know this, and thus to know the action and sufferings of Jesus as God’s reconciling Act, means to believe in Jesus, the God-Man.—Emil Brunner, The Christian Doctrine of Creation and Redemption, 338