The nature of a religion is determined by its conception of a Supreme Being. Of the religions of the world, only three are monotheistic—Judaism, Mohammedanism, and Christianity. The last of these is distinguished as holding a Trinity in the Godhead, three Persons and one God; and as holding the Incarnation of the Son, the second Person.
The Trinity is an eternal reality; but the Incarnation is a fact, something done in time. These two are the distinguishing and essential doctrines of Christianity. In this discussion, we assume that these doctrines, as expressed in the three great creeds of the Church, the Apostles', the Nicene, and the Athanasian, are true. Of the Trinity, we have no occasion to speak here except to note that the eternal constitution of the Godhead determines all Divine action. Without the threefold Personality, no Incarnation were possible. Nor do we attempt to define here how the union of the Divine and human could be effected, but believe that Jesus Christ was and is very God and very Man, and will continue to be so for ever. It has been truly said that the words "God was made Man" are perhaps of all others those which call for implicit acquiescence, and the renunciation of curiosity and inquisitive reasoning. It is apparent upon the face of it that this union is one of transcendent importance, not only for human history, but for the history of the universe, not only for the past, but for the present and future.
To take a creature nature into inseparable union with His own, is the most wonderful of all God's acts, that which is most difficult of intellectual comprehension, and yet that which lies at the basis of our knowledge of His character and of His purpose in Creation. It is not, like the creation of the worlds, an exercise of power and wisdom, and the product something external to Himself; but it is to take a created nature into the Godhead, or, as expressed in the Athanasian Creed, "taking of the manhood into God," and thus to establish such a relation of community between the Creator and the creature as would not otherwise be possible. God may build countless worlds in successive ages, He has but one Incarnate Son.
1 As I am assuming the truthfulness of the great creeds of the Church, I am not called to enter into any proofs of this. No Christian body has, so far as I know, ever called it in question, or affirmed a re-incarnation in other worlds as possible. Some individuals have indeed spoken of a deincarnation as effected by the Lord's death, which shows that they made no real distinction between Incarnation and theophany.
The Incarnation can never be repeated. The Creator and the creature are for ever united in the Person of the Son.1
As the Incarnate Son—Perfect God and Perfect Man,—He stands in a twofold relation, on the one side to God, and on the other to the creature, and these relations must be carefully distinguished. As the visible Image of the Invisible God, He is the Revealer; as made flesh, and taking the sins of men upon Himself, He is the Saviour. His work is one—and yet twofold.
It is ever to be kept in mind that Christianity has a scope far larger than that of redemption. When the Son has finished His work as Saviour of sinners, a transitory work, then His eternal work as the glorified Revealer of God does first and fully begin. But as He took upon Himself the office of the Revealer before the worlds were made, and as such was the Father's instrument in their creation, we must consider some preliminary points, and the first of these is the respective relations of the Father and the Son to the creative work, as taught us in the Scriptures.
If in the following discussions little mention is made of the Holy Spirit, the third Person of the Godhead, and of His work in creation and redemption, it is because of the desire to bring into special prominence the relations of the Father and Son. In the Incarnation itself, and in the Lord's work in the several stages of redemption, the co-operation of the Spirit was essential, and is clearly set forth in the Gospels and embodied in the Creeds, but we here accept results without asking how effected. The point to be kept in mind is that neither the Father nor the Spirit acted independently, but always in co-operation with the Son.