According to modern theology, the Son of God assumed our nature in order that through it, as a means to an end beyond himself, he might procure redemption for humanity as fallen in Adam. According to Mercersburg, the very assumption of that nature, in its sinless perfection, was itself the redemption of humanity. In him humanity stands redeemed already, as the source and fountain of the new race which proceeds from him. In him is our redemption, and by becoming one with him, it is all our own.
Samuel Miller, A Treatise on Mercersburg Theology; or, Mercersburg and Modern Theology Compared pg. 23
