Pope Leo XIII against Freemasonry

By Thomas V. Mirus ( bio - articles - email ) | Mar 05, 2026 | In Magisterium of Leo XIII

This is part of a series of articles and podcast episodes surveying the most important encyclicals of Pope Leo XIII.

It has been almost three hundred years since the Catholic Church first condemned Freemasonry—when on April 28, 1738, Pope Clement XII published a bull forbidding all Catholics to join Masonic lodges. The prohibition, on pain of excommunication, of Catholics from becoming Masons has remained ever since, with the Church clarifying multiple times in recent years that the ban is still in effect.

To many Catholics then and now, such a harsh declaration of enmity from the Church seems strange. Isn’t this just a silly prejudice against a benevolent fraternal organization?

To answer this question, we turn to Pope Leo XIII. Leo was the seventh pope to condemn Freemasonry, and wrote a total of four encyclicals on the topic. The latter three were focused specifically on the problem of Masonry in Italy, but the first, Humanum genus (1884), was the Church’s longest and most comprehensive explanation of her opposition to Freemasonry.

As Leo noted, despite the Church’s repeated warnings in the century and a half between the first condemnation and his own, Freemasonry had grown vastly in influence, gaining “such entrance into every rank of the State as to seem to be almost its ruling power”. The Masons, indeed, took prominent part in the negative political and social developments to which Leo would respond throughout his social teaching.

In particular, Freemasonry had been a strong driving force in the war of the Kingdom of Italy against the Papal States; key figures of the Risorgimento who worked for the destruction of the pope’s temporal reign were Masons. This effort resulted in the defeat of the Papal States in 1870, during the reign of Bl. Pius IX. In Leo’s time, the pope had no temporal reign, and would not again until the establishment of Vatican City as an independent state in the Lateran Treaty of 1929.

With Masons, previously more stealthy in their anti-Catholic aims, now openly and proudly seeking the Church’s destruction or at least its irrelevancy in every sphere of society, Leo could speak of Freemasonry as an especially organized and intentional manifestation of the ancient war of the kingdom of Satan against the Kingdom of God.

The secret society

It is important to note that even before considering the details of their doctrines or their political activities, Pope Leo condemned the very nature and structure of Freemasonry as a secret society. He recognized that there were different Freemasonic organizations, but asserted that they were essentially the same in their purpose.

In short, Leo objected to the following: Freemasonry’s rites and mysteries, its ultimate purposes and doctrines, and the names of its leaders were concealed not just from outsiders but from many members of the societies. Candidates for entry were made to swear oaths in advance that they would never reveal the membership or the matters discussed at meetings, while to strangers the Masons presented themselves as an innocuous but well-meaning group of cultured men intent on the betterment of the masses. On enrollment, the candidates promised total obedience to their superiors on pain of horrible penalties not excluding death, which was at times even meted out by assassins.

But the objective of Freemasonry, Leo says, is even more evil than the means it uses:

the utter overthrow of that whole religious and political order of the world which the Christian teaching has produced, and the substitution of a new state of things in accordance with their ideas, of which the foundations and laws shall be drawn from mere naturalism.

Naturalism

We have already discussed Leo’s condemnation of naturalism in his encyclical Libertas. In short, naturalism teaches the supremacy of human nature and reason, thus denying any religious revelation which surpasses the understanding of reason and is based on the authority of a teacher.

Naturalism, Leo says, leads the Freemasons to do the following:

• They advocate the complete separation of Church and State.
• They write and speak against the Catholic faith and the rights of the Church.
• They make laws which hinder the liberty of the Church in more or less subtle ways: laws which reduce the number and influence of the clergy, which interfere with or confiscate the property of the Church, and which break up the religious orders.
• In particular, they attack the Pope. First they got rid of his civil power, “the bulwark of his liberty and of his right” (in the conquest of the Papal States by the Kingdom of Italy). Now they advocate the abolition of the papacy itself as a spiritual power.

Some say that the Masons accept people from all religions, including Catholics, and don’t require Catholics to renounce their beliefs on entering. To this Leo responds:

First, in this way they easily deceive the simple-minded and the heedless, and can induce a far greater number to become members. Again, as all who offer themselves are received whatever may be their form of religion, they thereby teach the great error of this age—that a regard for religion should be held as an indifferent matter, and that all religions are alike. This manner of reasoning is calculated to bring about the ruin of all forms of religion, and especially of the Catholic religion, which, as it is the only one that is true, cannot, without great injustice, be regarded as merely equal to other religions.

And so, in their indifferentism:

• The Masons claim to believe in God, but they cannot agree among themselves even on things about God that can be known by reason alone, and they equally allow theists, atheists, and pantheists to enter their organizations.
• This encourages uncertainty about fundamental truths like the nature of the world as creation, the existence of divine Providence, the immortality of the soul, the afterlife—all of which robs society not only of supernatural, but even of natural order and goods.
• They advocate a secular morality, but this quickly leads to moral confusion and immorality.
• They deny original sin, and so have an inflated opinion of man’s ability to perfect himself by himself, without needing to constantly combat his own passions.
• This leads to social libertinism, which is even deliberately promoted by some people who think that the masses will be more easily controlled if they are lulled by vice and sensuality.

Many of Leo’s objections to naturalism in political and social life are familiar from his other encyclicals—the removal of God and the true religion from the State and from education of the young he deals with in Immortale Dei, the reduction of marriage to a civil contract regulated by the state in Arcanum, and political egalitarianism (rejection of authority, revolution, making an idol of democracy) in Libertas.

All this paves the way for something even worse, namely communism. Communists and socialists, Leo notes, hold many views in common with Freemasons, and the latter often support the plans of the former.

On egalitarianism, Leo profoundly challenges the political convictions of modern people in general and Americans in particular:

No one doubts that all men are equal one to another, so far as regards their common origin and nature, or the last end which each one has to attain, or the rights and duties which are thence derived. But, as the abilities of all are not equal, as one differs from another in the powers of mind or body, and as there are very many dissimilarities of manner, disposition, and character, it is most repugnant to reason to endeavor to confine all within the same measure, and to extend complete equality to the institutions of civic life. Just as a perfect condition of the body results from the conjunction and composition of its various members, which, though differing in form and purpose, make, by their union and the distribution of each one to its proper place, a combination beautiful to behold, firm in strength, and necessary for use; so, in the commonwealth, there is an almost infinite dissimilarity of men, as parts of the whole. If they are to be all equal, and each is to follow his own will, the State will appear most deformed; but if, with a distinction of degrees of dignity, of pursuits and employments, all aptly conspire for the common good, they will present the image of a State both well constituted and conformable to nature.

The ban

Leo concludes by reiterating the Church’s ban:

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.

And while it might be noted for accuracy that some Masonic organizations today do not have all the traits condemned by Leo (i.e., some accept only Christians, or are not as secretive about their laws), the Church has still kept up this ban, especially because of Masonry’s naturalism and religious indifferentism.

Interestingly, Leo promotes the Third Order Franciscans as a way of suppressing evil fraternities and leading men to true liberty, fraternity, and equality:

the liberty…of sons of God, through which we may be free from slavery to Satan or to our passions, both of them most wicked masters; the fraternity whose origin is in God, the common Creator and Father of all; the equality which, founded on justice and charity, does not take away all distinctions among men, but, out of the varieties of life, of duties, and of pursuits, forms that union and that harmony which naturally tend to the benefit and dignity of society.

He also suggests the St. Vincent de Paul Society and the restoration of the old workmen’s guilds as alternatives to Masonry. And above all, he asks the faithful to turn to prayer to combat this evil.

Masonic obsolescence through victory?

I may be wrong, but it seems like Freemasonry as an organized force is less relevant today than it was in Pope Leo XIII’s time. This is not due to any sunny outlook on my part; I think it is perhaps precisely because Masonry was so successful in spreading its ideology. Not only have many other organizations taken on some version of these ideas, but the Masonic worldview as laid out by Leo has totally pervaded and won out in the West. (Of course it is important to note, as the label “naturalism” implies, that these ideas are not exclusive to Masonry, being common to Enlightenment liberalism more generally.)

Even worse, I dare say that these beliefs are held, at least in part, by far too many high-ranking Churchmen today. This observation requires no conspiracy theory about present-day hierarchs being actual Masons. We need only listen to the way so many bishops and cardinals speak: their egalitarianism, the denial or downplaying of original sin implicit in their focus on improving man by secular initiatives, their religious indifferentism and their false ecumenism.

A Freemasonic idea which Leo XIII did not mention, but which is worth bringing up in conclusion, is that of “the Brotherhood of Man under the Fatherhood of God”. This may sound Catholic, but it is not, and sadly, our late Pope Francis (God rest his soul) could at times put an emphasis on human fraternity that seemed more Masonic than Christian. (Again, this is not remotely to suggest that he was a literal Freemason, but to comment on how these ideas have spread to distort Christianity into a kind of religion of humanity.)

It is true that the human race is a family in terms of our shared nature and ancestry, but we are not all brothers in a spiritual sense. We are all creatures of God, and as Leo himself alluded above, this means we can speak loosely about God being the “Father of all”, but it is also true in an important sense that we are not all children of God—certainly not in the Freemasonic sense, in which God is whatever god someone might happen to believe in. The Church has always taught that the only way to become a child of God is through baptism. Indeed, the traditional Catholic teaching reflected in the old rite of baptism is that those who are not baptized are under the dominion of the devil.

The preoccupation of many high-ranking Church officials with ensuring human fraternity, a global peace, justice, and harmony not predicated on the necessity of global conversion, at times seems to involve an implicit rejection of that traditional doctrine. If, in the profusion of messages and documents from popes, bishops, dicasteries, and synods, the salt seems to have lost its savor, it is likely because they have forgotten the bracing truth that those who do not belong to Christ belong to Satan. That means that peace, harmony and brotherhood cannot be brought about by secular universalism, but only through unity of faith.

I also discussed Humanum Genus on the Catholic Culture Podcast: