Christ founded the Church with two great figures of speech; in the final words to the Apostles who received authority to found it. The first was the phrase about founding it on Peter as on a rock; the second was the symbol of the keys. About the meaning of the former there is naturally no doubt in my own case; but it does not directly affect the argument here save in two more secondary aspects. It is yet another example of a thing that could only fully expand and explain itself afterwards, and even long afterwards. And it is yet another example of something the very reverse of simple and self-evident even in the language, in so far as it described a man as a rock when he had much more the appearance of a reed. But the other image of the keys has an exactitude that has hardly been exactly noticed. The keys have been conspicuous enough in the art and heraldry of Christendom; but not every one has noted the peculiar aptness of the allegory. We have now reached the point in history where something must be said of the first appearance and activities of the Church in the Roman Empire; and for that brief description nothing could be more perfect than that ancient metaphor. The Early Christian was very precisely a person carrying about a key, or what he said was a key. The whole Christian movement consisted in claiming to possess that key. It was not merely a vague forward movement, which might be better represented by a battering-ram. It was not something that swept along with it similar and dissimilar things, as does a modern social movement. As we shall see in a moment, it rather definitely refused to do so. It definitely asserted that there was a key and that it possessed that key and that no other key was like it; in that sense it was as narrow as you please. Only it happened to be the key that could unlock the prison of the whole world; and let in the white daylight of escape. The creed was like a key in three respects; which can be most conveniently summed up under this symbol. First, a key is above all things a thing with a shape. It is a thing that depends entirely upon keeping its shape. The Christian creed is above all things the philosophy of shapes and the enemy of shapelessness. That is where it differs from all that formless infinity, Manichean or Buddhist, which makes a sort of pool of night in the dark heart of Asia; the ideal of uncreating all the creatures. That is where it differs also from the analogous vagueness of mere evolutionism; the idea of creatures constantly losing their shape. A man told that his solitary latchkey had been melted down with a million others into a Buddhistic unity would be annoyed. But a man told that his key was gradually growing and sprouting in his pocket, and branching into new wards or complications, would not be more gratified.