it is equally true that so soon as the Church has succeeded in influencing the world, it is the turn of the world to influence the Church. It is not too much to say that the history of the Church is alternately the history of the Church affecting the world and of the Church being affected by the world. The spirit of Christianity was to transform the world. In early times it aimed at doing so from within, but when it became the recognised religion of the Roman Empire, it had to undertake the organisation of the Church and the world. Then as soon as the Church as an organised institution had affected the masses of men, it in its turn was affected by them. An institution may itself remain the same, but the spirit which inspires it tends undoubtedly to fall to the level of the mass whom it has succeeded in including within its system. So we are not surprised to find that the great epoch of the Church's history during which it succeeded in converting the barbarians was followed by a time when the institutions, the customs, the very modes of thought of those rude peoples in their turn affected the Church. The development of the Church followed the lines of the general development of civilisation, and with the feudal system there grew up a feudalised Church, modified no doubt by the idea of imperialism and by the teutonic spirit of independence. But the Church as it became feudalised lost its own proper nature and spirit. It tended to become merely a part of the State, an instrument in the hands of the great lords, to lose its spirituality.
In face of this danger came the reformation of the eleventh century, which centred round Hildebrand,
