That is perhaps the mightiest of the mysteries of the cave. It is already apparent that though men are said to have looked for hell under the earth, in this case it is rather heaven that is under the earth. And there follows in this strange story the idea of an upheaval of heaven. That is the paradox of the whole position; that henceforth the highest thing can only work from below. Royalty can only return to its own by a sort of rebellion. Indeed the Church from its beginnings, and perhaps especially in its beginnings, was not so much a principality as a revolution against the prince of the world. This sense that the world had been conquered by the great usurper, and was in his possession, has been much deplored or derided by those optimists who identify enlightenment with ease. But it was responsible for all that thrill of defiance and a beautiful danger that made the good news seem to be really both good and new. It was in truth against a huge unconscious usurpation that it raised a revolt, and originally so obscure a revolt. Olympus still occupied the sky like a motionless cloud moulded into many mighty forms; philosophy still sat in the high places and even on the thrones of the kings, when Christ was born in the cave and Christianity in the catacombs. In both cases we may remark the same paradox of revolution; the sense of something despised and of something feared. The cave in one aspect is only a hole or corner into which the outcasts are swept like rubbish; yet in the other aspect it is a hiding-place of something valuable which the tyrants are seeking like treasure. In one sense they are there because the innkeeper would not even remember them, and in another because the king can never forget them. We have already noted that this paradox appeared also in the treatment of the early Church. It was important while it was still insignificant, and certainly while it was still impotent. It was important solely because it was intolerable; and in that sense it is true to say that it was intolerable because it was intolerant. It was resented, because, in its own still and almost secret way, it had declared war. It had risen out of the ground to wreck the heaven and earth of heathenism. It did not try to destroy all that creation of gold and marble; but it contemplated a world without it. It dared to look right through it as though the gold and marble had been glass. Those who charged the Christians with burning down Rome with firebrands were slanderers; but they were at least far nearer to the nature of Christianity than those among the moderns who tell us that the Christians were a sort of ethical society, being martyred in a languid fashion for telling men they had a duty to their neighbours, and only mildly disliked because they were meek and mild.