With reason, then, the common opinion of mankind, little affected by the few dissentients who have contended for the opposite view, has found in the careful study of nature, and in the laws of nature, the foundations of the division of property, and the practice of all ages has consecrated the principle of private ownership, as being pre-eminently in conformity with human nature, and as conducing in the most unmistakable manner to the peace and tranquility of human existence.
Pope Leo XIIIOnce the demands of necessity and propriety have been met, the rest that one owns belongs to the poor.
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.
Pope Leo XIIIThe death sentence is a necessary and efficacious means for the Church to attain its end when rebels act against it and disturbers of the ecclesiastical unity, especially obstinate heretics and heresiarchs, cannot be restrained by any other penalty from continuing to derange the ecclesiastical order and impelling others to all sorts of crime ... When the perversity of one or several is calculated to bring about the ruin of many of its children it is bound effectively to remove it, in such wise that if there be no other remedy for saving its people it can and must put these wicked men to death.
Pope Leo XIIIFor when men know they are working on what belongs to them, they work with far greater eagerness and diligence. Nay, in a word, they learn to love the land cultivated by their own hands, whence they look not only for food but for some measure of abundance for themselves and their dependents. All can see how much this willing eagerness contributes to an abundance of produce and the wealth of a nation.
Pope Leo XIIIAs Our Predecessors have many times repeated, let no man think that he may for any reason whatsoever join the Masonic sect, if he values his Catholic name and his eternal salvation as he ought to value them. Let no one be deceived by a pretense of honesty. It may seem to some that Freemasons demand nothing that is openly contrary to religion and morality; but, as the whole principle and object of the sect lies in what is vicious and criminal, to join with these men or in any way to help them cannot be lawful
Pope Leo XIII