Hence from all we have hitherto said, it is clear beloved Catholics that we cannot approve the opinions which some [Protestants, Jews, and other heretics] comprise under the head of Americanism [freedom].
Pope Leo XIIIOur Lord came to the aid of each great tribulation with a special devotion. The present and future tribulations of the Church and of nations are greater than at any other period, and this persecution is more dangerous than those of previous times. Hence, the devotion which God sends to the succor of His Church and of the nations at the present time is the devotion to the Most Holy Eucharist. It is the highest of all devotions.
Pope Leo XIIIIf unbridled licence of speech and writing be granted to all, nothing will remain sacred and inviolate; even the highest and truest mandates of nature, justly held to be the common and noblest heritage of the human race, will not be spared. Thus, truth being gradually obscured by darkness, pernicious and manifold error, as too often happens, will easily prevail.
Pope Leo XIIITo this must be added that the hiring of labor and the conduct of trade are concentrated in the hands of comparatively few; so that a small number of very rich men have been able to lay upon the teeming masses of the laboring poor a yoke little better than that of slavery itself.
Pope Leo XIIIThe present age handed over the workers, each alone and defenseless, to the unbridled greed of competitors... so that a very few and exceedingly rich men have laid a yoke of almost slavery on the unnumbered masses of non-owning workers.
Pope Leo XIIINot only, in strict truth, was marriage instituted for the propagation of the human race, but also that the lives of husbands and wives might be made better and happier. This comes about in many ways: by their lightening each other's burdens through mutual help; by constant and faithful love; by having all their possessions in common; and by the heavenly grace which flows from the sacrament.
Pope Leo XIII