In the course of Christian history a good deal of time has been occupied in the discussion of the metaphysical question of the complex unity of the divine nature; and the result has been the doctrine of the Trinity, a conception which, it has been claimed, at once satisfies and transcends the operations of the human intellect. Most non-theological modern minds are, however, somewhat suspicious of the doctrine of the Trinity; it seems rather too speculative and too remote from ordinary ways of thinking to possess much real value. But this is quite a mistake. We cannot dispense with the doctrine of the Trinity, for it, or something like it, is implied in the very structure of the mind. It belongs to philosophy even more than to religion, and to the sphere of ethics not less. I daresay even the man in the street knows, quite as certainly as the man in the schools, that a metaphysical proposition underlies the doing of every moral act, even though it may never be expressed. All thinking starts with an assumption of some kind, and without an assumption thought is impossible. This is just as true of the strictest scientific processes as it is of deductive reasoning, and indeed it is interesting to watch the way in which within recent years idealistic philosophy and empirical science have joined hands. Does physical science, then, imply the doctrine of the Trinity? Yes, unquestionably it does, after a fashion, for it starts with an assumption which takes it for granted. Perhaps this would be news to Professor Ray Lankester, and such as he, but I think I could convince them that I am right if I had them face to face. To use the mind at all we have to assume this doctrine even though we may not actually formulate it. Christianity did not invent it; it clarified and defined it, but in principle it is as old as the exercise of human reason.

+The basal assumption of thought.+—After making a comprehensive assertion of this kind I suppose I am bound to justify it, and I do not shrink from the task. I say that all thinking starts with an assumption of some kind, and exact thought requires that that assumption shall be the simplest possible, the irreducible minimum beneath which we cannot get. Now when we start thinking about existence as a whole and ourselves in particular, we are compelled to assume the infinite, the finite, and the activity of the former within the latter. In other words we have to postulate God, the universe, and God's operation within the universe. Look at these three conceptions for a moment and it will be seen that every one of them implies the rest; they are a Trinity in unity. The primordial being must be infinite, for there cannot be a finite without something still beyond it. We know, too, that to our experience the universe is finite; we can measure, weigh, and analyse it—an impossible thing to do with an infinite substance. And yet if we think of infinite and finite as two entirely distinct and unrelated modes of existence, we find ourselves in an impossible position, for the infinite must be that outside of which nothing exists or can exist; so of course we are compelled to think of the infinite as ever active within the finite, the source of change and motion, the exhaustless power which makes possible the very idea of development from simplicity to complexity. If the universe were complete in itself, change would not occur, and a cosmic process, evolutionary or otherwise, would be inconceivable. Here, then, we have the basal factors of any true theology, philosophy, or science. Readers of Haeckel's "Riddle of the Universe" will note that that eminent materialist, who professes to do away with the very idea of God, takes these factors for granted; and yet I suppose he would object to being told that he believes in the doctrine of the Trinity. But he does, for he begins by assuming infinite space filled to the farthest with matter ponderable and imponderable, and forthwith proceeds to weigh, measure, and divide the latter as though it were finite! Here are two terms of the doctrine of the Trinity at once. We get the third as soon as Professor Haeckel sets to work to explain the cosmic process, for as he does so he is all the while taking for granted that the infinite is pressing in and up through the finite, evolving beauty and order, light and life.

+The moral basis of the doctrine.+—But it may be contended that these bare bones of the doctrine of the Trinity are not the doctrine as it enters into spiritual experience. I admit the fact while asserting strongly that but for this framework of intellectual necessity the doctrine would be unknown to faith and morals. It is sometimes stated that the doctrine of the Trinity was formulated in order to account for Jesus, but that is only incidentally true. Its framers took the materials for it over from Greek thought, and even Greek thought probably inherited it from an older civilisation still, if indeed there were any necessity to inherit it. I contend that if we had never heard of the doctrine in connection with Jesus, we should have to invent it now in order to account for ourselves and the wondrous universe in which we live.

Unquestionably, however, it is from the point of view of religion and morals that the doctrine has most significance, and therefore has become indissolubly associated with the personality of Jesus; and it is easy to see how this has come about. Thinkers have always been compelled to construe the universe in terms of the highest known to man, namely, his own moral nature. It was natural, therefore, that while they thought of the universe as an expression of God, they should think of it as the expression of that side of His being which can only be described as the ideal or archetypal manhood. The infinite being of God is utterly incomprehensible to a finite mind, and in regard to it the most devout saint is as much an agnostic as the most convinced materialist. But we are justified in holding that whatever else He may be God is essentially man, that is, He is the fount of humanity. There must be one side, so to speak, of the infinitely complex being of God in which humanity is eternally contained and which finds expression in the finite universe. Humanity is not a vague term; we have already seen something of what it is. We ought not to interpret it in terms of the primeval savage, or even of average human nature to-day, but in terms of what we have come to feel is its highest expression, and that is Jesus. If we think therefore of the archetypal eternal divine Man, the source and sustenance of the universe, and yet transcending the universe, we cannot do better than think of Him in terms of Jesus; Jesus is the fullest expression of that eternal divine Man on the field of human history. Here, then, we have the first and second factors in the doctrine of the Trinity morally and spiritually construed.

+The divine Man.+—The idea of a divine Man, the emanation of the infinite, the soul of the universe, the source and goal of all humanity, is ages older than Christian theology. It can be traced in Babylonian religious literature, for instance, at a period older even than the Old Testament. It played a not unimportant part in Greek thought, and Philo of Alexandria, a contemporary of Jesus, works it out in some detail in his religio-philosophic system, which aimed to combine the wide outlook of Greek culture with the high seriousness of Hebrew religion. It is a true, indeed an inevitable, conception, if we hold anything like a consistent view of the immanence of God in His universe. With what God have we to do except the God who is eternally man? This aspect of the nature of God has been variously described in the course of its history. It has been called the Word, the Son, and, as we have seen, the second person in the Trinity. For various reasons I prefer to call it—or rather Him—the eternal Christ. I do this because, for one thing, the word "Christ" is a living word with a clearly marked ethical content and a great religious value. Originally, of course, it was but the Greek equivalent of the Hebrew Messiah, and meant the "anointed one," the person chosen for a special divine work. But in the New Testament, especially the writings of St. Paul, as well as all Christian history through, it is associated on the one hand with the personality of Jesus, and, on the other, with the fontal or ideal Man who contains and is expressed in all human kind. According to the New Testament writers, Jesus was and is the Christ, but in His earthly life His consciousness of the fact was limited. But, as we have come forth from this fontal manhood, we too must be to some extent expressions of this eternal Christ; and it is in virtue of that fact that we stand related to Jesus, and that the personality of Jesus has anything to do with us. Here is where the value of our belief in the interaction of the higher and the lower self comes in. Fundamentally our being is already one with that of the eternal Christ, and faith in Jesus is faith in Him. Jesus is not one being and the Christ another; the two are one, and Jesus seems to have known it during His earthly ministry. He lived His life in such a way as to reveal the very essence of the Christ nature. He is therefore central for us, and we are complete in Him. Here is the goal of all moral effort—Christ. Here, too, is the highest reach of the religious ideal—Christ. "For the life was manifested, and we have seen it, and bear witness, and shew unto you that eternal life, which was with the Father, and was manifested unto us."

+The Christ of St. Paul.+—I am persuaded that we have here the key to the Christology of that great thinker and preacher, the apostle Paul. It is this ideal or eternal Christ who is the object of his faith and devotion. He even goes so far as to warn his readers not to dwell too much upon the limited earthly Jesus, but upon His true being in the eternal reality: "Wherefore henceforth know we no man after the flesh; yea, though we have known Christ after the flesh, yet now henceforth know we Him no more." He does not say, "To me to live is Jesus," but, "To me to live is Christ." If ever there was a Christian who really loved Jesus with passionate and whole-hearted devotion, it was the apostle Paul, but he says almost nothing about the earthly ministry of his Lord. He seems to have had a vivid impression as to what the character of Jesus was really like, and he gave himself up to the worship of this with all his heart; but he does not draw for us any of the beautiful gospel pictures of the Jesus in the peasant's dress who taught on the hillsides of Galilee, went about doing good, was a welcome guest in the home at Bethany, lived a true human life, and died a shameful death. Paul always thought of Him, and truly, as the Lord who came down from heaven, but he does not draw a sharp line of distinction between Him and the rest of humanity. He calls Jesus "the first-born among many brethren." He speaks of the summing up of all things in Christ, and of the final consummation when God shall be all in all. Here is the New Theology with a vengeance. Paul requires to be rescued from the inadequate and distorting interpretations his thought has received in the course of its history. He brought this conception of the eternal Christ into Christianity from pre-Christian thought, saw it ideally revealed in Jesus, and then bade mankind respond to it and realise it to be the true explanation of our own being. Sometimes he appears to deviate from this view, and to say things inconsistent with it, but that we need not mind; he saw it, and that is enough. It forms the foundation of his gospel.