As long as a tree or an animal lives it continues to grow. An arrest of growth is the first symptom of the decline of life. Fulness of life, therefore, as the essential character of Christianity, should produce a constant development and progress; and this we find to be the case. Other religions have their rise, progress, decline, and fall, or else are arrested and become stationary. The religions of Persia, Egypt, Greece, Rome, Scandinavia, have come to an end. As ethnic religions, they shared the fortunes of the race or nation with which they were associated. The systems of Confucius, of the Buddha, of Brahmanism, of Judæa, of Mohammed, are arrested. They remain stationary. But, thus far, Christianity and Christendom advance together. Christianity has developed; out of its primitive faith, several great theologies, the mediæval Papacy, Protestantism, and is now evidently advancing into new and larger forms of religious, moral, and social activity.
The fact of a fulness of divine and human life in Jesus took form in the doctrines of the incarnation and the Trinity. The fact of the reconciling and uniting power of this life took form in the doctrine of the atonement. Both of these doctrines are illogical and false, in their form, as church doctrines. But both of them represent most essential facts. We have seen the truths in the doctrines of incarnation and the Trinity. The truth in the atonement is, as the word itself signifies, the at-one-making power of the Gospel. The reconciliation of antagonist truths and opposing tendencies, which philosophy has always unsuccessfully endeavored to state in theory, Christianity accomplishes in practice.
Christianity continually reproduces from its depths of life a practical faith in God, both as law and as love, in man, both as a free and yet as a providentially guided being. It gives us God as unity and as variety, as the substance and as the form of the world. It states the reality of evil as forcibly as any system of dualism, and yet produces a practical faith in good as being stronger than evil and sure to conquer it. In social life it reconciles the authority of human law with the freedom of individual thought and action. In the best Christian governments, we find all the order which a despotism can guarantee, with all the freedom to which a democracy can aspire. No such social organization is to be found outside of Christendom. How can this be, unless it is somehow connected with Christianity?
The civilization of Christendom consists in a practical reconciliation of antagonist tendencies. It is a "pleroma" in social life, a fulness of concord, a harmony of many parts. The harmony is indeed by no means complete, for the millennium has not arrived. As yet the striking feature of Christendom is quantity, power, variety, fulness; not as yet co-operation, harmony, peace, union. Powers are first developed, which are afterward to be harmonized. The sword is not yet beaten into a ploughshare, nor has universal peace arrived. Yet such is the inevitable tendency of things. As knowledge spreads, as wealth increases, as the moral force of the world is enlarged, law, more and more, takes the place of force. Men no longer wear swords by their sides to defend themselves from attack. If attacked, they call the policeman. Towns are no longer fortified with walls, nor are the residences of noblemen kept in a state of defence. They are all folded in the peaceful arms of national law. So far the atonement has prevailed. Only nations still continue to fight; but the time is at hand when international law, the parliament of the world, the confederation of man, shall take the place of standing armies and iron-clad navies.
So, in society, internal warfare must, sooner or later, come to an end. Pauperism and crime must be treated according to Christian methods. Criminals must be reformed, and punishment must be administered in reference to that end. Co-operation in labor and trade must take the place of competition. The principles by means of which these vast results will be brought about are already known; the remaining difficulties are in their application. Since slavery fell in the United States, one great obstacle to the progress of man is removed. The next social evils in order will be next assailed, and, one by one, will be destroyed. Christianity is becoming more and more practical, and its application to life is constantly growing more vigorous and wise.
The law of human life is, that the development of differences must precede their reconciliation. Variety must precede harmony, analysis must prepare the way for synthesis, opposition must go before union. Christianity, as a powerful stimulus applied to the human mind, first develops all the tendencies of the soul; and afterward, by its atoning influence on the heart, reconciles them. Christ is the Prince of Peace. He came to make peace between man and God, between man and man, between law and love, reason and faith, freedom and order, progress and conservatism. But he first sends the sword, afterward the olive-branch. Nevertheless, universal unity is the object and end of Christianity.