[The disease] might almost as truly be called the mistake of being natural; and it was a very natural mistake. The Greeks, the great guides and pioneers of pagan antiquity, started out with the idea of something splendidly obvious and direct; the idea that if a man walked straight ahead on the high road of reason and nature, he would come to no harm; especially if he was, as the Greek was, eminently enlightened and intelligent...
The wisest men in the world set out to be natural; and the most unnatural thing in the world was the very first thing they did. The immediate effect of saluting the sun and the sunny sanity of nature was a perversion spreading like a pestilence. The greatest and even the purest philosophers could not apparently avoid this low sort of lunacy. Why? ... The truth is people who worship health cannot remain healthy on the point. When Man goes straight he goes crooked. When he follows his nose he manages somehow to put his nose out of joint, or even to cut off his nose to spite his face; and that in accordance with something much deeper in human nature than nature-worshippers could ever understand.
It was the discovery of that deeper thing, humanly speaking, that constituted the conversion to Christianity. There is a bias in a man like the bias on a bowl; and Christianity was the discovery of how to correct the bias and therefore hit the mark. There are many who will smile at the saying; but it is profoundly true to say that the glad good news brought by the Gospel was the news of original sin.
Rome rose at the expense of her Greek teachers largely because she did not entirely consent to be taught these tricks. She had a much more decent tradition; but she ultimately suffered from the same fallacy in her religious tradition; which was necessarily in no small degree the heathen tradition of nature worship. What was the matter with the whole heathen civilisation was that there nothing for the mass of men in the way of mysticism... Long before the end, we find nature-worship inevitably producing things that are against nature.
What had happened to the human imagination, as a whole, was that the whole world was coloured by dangerous and rapidly deteriorating passions; by natural passions becoming unnatural passions. Thus the effect of treating sex as only one innocent natural thing was that every other innocent natural thing became soaked and sodden with sex. For sex cannot be admitted to a mere equality among elementary emotions or experiences like eating and sleeping. The moment sex ceases to be a servant it becomes a tyrant. There is something dangerous and disproportionate in its place in human nature, for whatever reason; and it does really need a special purification and dedication...
It was not so much that the pagan world was wicked as that it was good enough to realise that its paganism was becoming wicked, or rather it was on the logical high road to wickedness. I mean that there was no future for "natural magic"; to deepen it was only to darken it into black magic. There was no future for it; because in the past it had only been innocent because it was young. We might say it had only been innocent because it was shallow. Pagans were wiser that paganism; that is why the pagans became Christians. Thousands of them had philosophy and family virtues and military honour to hold them up; but by this time the purely popular thing called religion was certainly dragging them down. When this reaction against the evil is allowed for, it is true to repeat that it was an evil that was everywhere. In another and more literal sense its name was Pan.
It was no metaphor to say that these people needed a new heaven and a new earth; for they had really defiled their own earth and even their own heaven. How could their case be met by looking at the sky, when erotic legends were scrawled in stars across it; how could they learn anything from the love of birds and flowers after the sort of love stories that were told of them? It is impossible here to multiply evidences...
Nothing could purge this obsession but a religion that was literally unearthly.
It was no good telling such people to have a natural religion full of stars and flowers; there was not a flower or even a star that had not been stained. They had to go into the desert where they could find no flowers or even into the cavern where they could see no stars. Into that desert and that cavern the highest human intellect entered for some four centuries; and it was the very wisest thing it could do.
Nothing but the stark supernatural stood up for its salvation; if God could not save it, certainly the gods could not. The early Church called the gods of paganism devils; and the Early Church was perfectly right. Whatever natural religion may have had to do with their beginnings, nothing but fiends now inhabited those hollow shrines. Pan was nothing but panic. Venus was nothing but venereal vice. I do not mean for a moment, of course, that all the individual pagans were of this character even to the end; but it was as individuals that they differed from it... It was no good to preach natural religion to people to whom nature had grown as unnatural as any religion. They knew much better than we do what was the matter with them and what sort of demons at once tempted and tormented them; and they wrote across that great space of history the text; 'This sort goeth not out but by prayer and fasting.'
Now the historical importance of St. Francis and the transition from the twelfth to the thirteenth centuries, lies in the fact that they marked the end of this expiation. Men at the close of the dark Ages may have been rude and unlettered and unlearned in everything but wars with heathen tribes, more barbarous than themselves, but they were clean. They were like children; the first beginnings of their rude arts have all the clean pleasure of children.
We have to conceive them in Europe as a whole living under little local governments, feudal in so far as they were a survival of fierce wars with the barbarians, often monastic and carrying a far more friendly and fatherly character, still faintly imperial as far as Rome still ruled as a great legend.
But in Italy something had survived more typical of the finer spirit of antiquity; the republic, Italy, was dotted with little states, largely democratic in their ideals, and often filled with real citizens. But the city no longer lay open as under the Roman peace, but was pent in high walls for defence against feudal war and all the citizens had to be soldiers.
One of these stood in a steep and striking position on the wooded hills of Umbria; and its name was Assisi. Out of its deep gate under its high turrets was to come the message that was the gospel of the hour,
'Your warfare is accomplished, your iniquity is pardoned.'