Historically it is easy to understand the dislike which the Church has shown for economic liberty and political Liberalism in any form. Liberalism is the flower of that rational enlightenment which dealt a death blow to the regime of the old Church and from which modern historical criticism has sprung. It was Liberalism that undermined the power of the classes that had for centuries been closely bound up with the Church. It transformed the world more than Christianity had ever done. It restored humanity to the world and to life. It awakened forces which shook the foundations of the inert traditionalism on which Church and creed rested. The new outlook caused the Church great uneasiness, and it has not yet adjusted itself to even the externals of the modern epoch. True, the priests in Catholic countries sprinkle holy water on newly laid railways and dynamos of new power stations, but the professed Christian still shudders inwardly at the workings of a civilization which his faith cannot grasp. The Church strongly resented modernity and the modern spirit. What wonder, then, that it allied itself with those whom resentment had driven to wish for the break-up of this wonderful new world, and feverishly explored its well-stocked arsenal for the means to denounce the earthly struggle for work and wealth. The religion which called itself the religion of love became a religion of hatred in a world that seemed ripe for happiness. Any would-be destroyers of the modern social order could count on finding a champion in Christianity.

(from his book on Socialism)