During the first few centuries the Church spread rapidly, not only throughout the more civilised parts of the Roman Empire, but also amongst the rough Celts of Britain and the fierce Teutons of Germany. We may well ask, why did it cease to spread, and why are so many lands still lying in darkness? Since Christ came to be the Saviour of the world, how is it that there are so many millions of Buddhists and Hindoos in Asia, that to this day it is said that not one-third of the inhabitants of the world are; Christians? The answer is, alas! clear. The unity of the One Universal Church of Christ has not been maintained in the full and perfect manner described in our Lord's Prayer, "That they all may be one, as Thou, Father, art in Me, and I in Thee, that they also may be one in Us" (S. John xvii. 21). Christians have lost the sense of brotherhood, which should bind them all together in Christ, of whatsoever nation or language they may be. The Church has ceased to move with the irresistible power of one mighty army, acting with one mind for the glory of God. All thoughtful subjects of "The Kingdom of Heaven" must lament this state of disunion and weakness. And men are striving in different, and in some cases opposite ways, to bring about re-union. But when we begin to ask, What is the remedy? we find that we are facing a mighty problem. God's loving purpose for the salvation of the world has been marred by man's wilfulness. His Kingdom, which might have been irresistible and have won the whole world for Christ, has been split up into many portions, which have been opposing and weakening one another, instead of fighting His enemies. How can these portions, after centuries of disunion, be reunited into one? How can the mischief be undone? It is beyond the power of man. Yet at the same time we can see that there are certain things which all can do to advance the object in view, and to promote re-union at least in our own National Church at home, if not also between the different branches of Christ's Holy Church[20] throughout the world. But to do so, two things are clearly necessary. One thing is to have a clear grasp of the principle which runs through the whole teaching of the Bible,--that Christ came to found a Kingdom. And the other is to desire unity. If all desired unity, the desired result would certainly be accomplished.