There is one unprecedented feature of our own post-Christian civilization which, in spite of being a rather superficial feature, has a certain importance in this connection. In the course of its expansion our modern Western secular civilization has become literally world-wide and has drawn into its net all other surviving civilizations as well as primitive societies. At its first appearance, Christianity was provided by the Graeco-Roman civilization with a universal state, in the shape of the Roman Empire with its policed roads and shipping routes, as an aid to the spread of Christianity round the shores of the Mediterranean. Our modern Western secular civilization in its turn may serve its historical purpose by providing Christianity with a completely world-wide repetition of the Roman Empire to spread over. We have not quite arrived at our Roman Empire yet, though the victor in this world may be the founder of it. But long before a world is unified politically, it is unified economically and in other material ways; and the unification of our present world has long since opened the way for St. Paul, who once travelled from the Orontes to the Tiber under the aegis of the Pax Romana, to travel on from the Tiber to the Mississippi to the Yangtse; while Clement’s and Origen’s work of infusing Greek philosophy into Christianity at Alexandria might be emulated in some city of the Far East by the infusion of Chinese philosophy into Christianity.
This intellectual feat has indeed been partly performed already. One of the greatest of modern missionaries and modern scholars, Matteo Ricci, who was both a Jesuit father and a Chinese literatus, set his hand to that task before the end of the sixteenth century of the Christian era. It is even possible that as, under the Roman Empire, Christianity drew out of and inherited from the other Oriental religions the heart of what was best in them, so the present religions of India and the form of Buddhism that is practiced to-day in the Far-East may contribute new elements to be grafted onto Christianity in days to come. And then one may look forward to what may happen when Caesar’s empire decays –for Caesar’s empire always does decay after a run of a few hundred years. What may happen is that Christianity may be left as the spiritual heir of all the other higher religions, from the post-Sumerian rudiment of one in the worship of Tammuz and Ishtar down to those that in A.D. 1948 are still living separate lives side by side with Christianity, and of all the philosophies from Ikhnaton’s to Hegel’s; while the Christian Church as an institution may be left as the social heir of all the other churches and all the civilizations.
That side of the picture brings one to another question which is both always old and always new –the question of the relation of the Christian Church to the Kingdom of Heaven. We seem to see a series of different kinds of society succeeding one another in this world. As the primitive species of societies has given place to a second species known as the civilizations within the brief period of the last six thousand years, so this second species of local and ephemeral societies may perhaps give place in its turn to a third species embodied in a single world-wide and enduring representative in the shape of the Christian Church. If we can look forward to that. we shall have to ask ourselves this question:Supposing that this were to happen would it mean that the Kingdom of Heaven would then have been established on Earth?