Liberty, in so far as it is a virtue perfecting man, should be occupied with that which is true and that which is good; but the foundation of that which is true and that which is good cannot be changed at the pleasure of man, but remains ever the same, nor indeed is it less unchangeable than nature herself. If the mind assent to false opinions, if the will choose for itself evil, and apply itself thereto, neither attains its perfection, but both fall from their natural dignity, and both lapse by degrees into corruption. Whatever things, therefore, are contrary to virtue and truth, these things it is not right to place in the light before the eyes of men, far less to defend by the favor and tutelage of the laws. A well-spent life is the only path to that heaven whither we all direct our steps; and on this account the State departs from the law and custom of nature if it allows the license of opinions and of deeds to run riot to such a degree as to lead minds astray with impunity from the truth, and hearts from the practice of virtue.
But to exclude the Church which God Himself has constituted from the business of life, from the laws, from the teaching of youth, from domestic society, is a great and pernicious error. A well-regulated State cannot be when religion is taken away; more than needs be, perhaps, is now known of what sort of a thing is in itself, and whither tends that philosophy of life and morals which men call civil. The Church of Christ is the true teacher of virtue and guardian of morals; it is that which keeps principles in safety, from which duties are derived, and by proposing most efficacious reasons for an honest life, it bids us not only fly from wicked deeds, but rule the motions of the mind which are contrary to reason when it is not intended to reduce them to action. But to wish the Church in the discharge of its offices to be subject to the civil power is a great rashness, a great injustice. If this were done order would be disturbed, since things natural would thus be put before those which are above nature; the multitude of the good whose common life, if there be nothing to hinder it, the Church would make complete, either disappears or at all events is considerably diminished, and besides, a way is opened to enmities and conflicts—how great the evil which they bring upon each order of government the event has too frequently shown.
Such doctrines are not approved by human reason, and are of the greatest gravity as regards civil discipline, the Roman Pontiffs our predecessors—well understanding what the apostolic office required of them—by no means suffered to go forth without condemnation. Thus Gregory XVI., by Encyclical Letter, beginning Mirare vos, of August 15, 1832, inveighed with weighty words against those doctrines which were already being preached, namely, that in divine worship no choice should be made; and that it was right for individuals to judge of religion according to their personal preferences, that each man's conscience was to himself his sole sufficient guide, and that it was lawful to promulgate whatsoever each man might think, and so make a revolution in the State. Concerning the reasons for the separation of Church and State, the same Pontiff speaks thus: "Nor can we hope happier results either for religion or the government, from the wishes of those who are eagerly desirous that the Church should be separated from the State, and the mutual good understanding of the sovereign secular power and the sacerdotal authority be broken up. It is evident that these lovers of most shameless liberty dread that concord which has always been fortunate and wholesome, both for sacred and civil interests." To the like effect Pius IX., as opportunity offered, noted many false opinions which had begun to be of great strength, and afterward ordered them to be collected together in order that in so great a conflux of errors Catholics might have something which, without stumbling, they might follow.
From these decisions of the Popes it is clearly to be understood that the origin of public power is to be sought from God Himself and not from the multitude; that the free play for sedition is repugnant to reason; that it is a crime for private individuals and a crime for States to observe nowhere the duties of religion or to treat in the same way different kinds of religion; that the uncontrolled right of thinking and publicly proclaiming one's thoughts is not inherent in the rights of citizens, nor in any sense to be placed among those things which are worthy of favor or patronage. Similarly it ought to be understood that the Church is a society, no less than the State itself, perfect in kind and right, and that those who exercise sovereignty ought not to act so as to compel the Church to become subservient or inferior to themselves, or suffer her to be less free to transact her own affairs or detract aught from the other rights which have been conferred upon her by Jesus Christ. But in matters however in complex jurisdiction, it is in the highest degree in accordance with nature and also with the counsels of God—not that one power should secede from the other, still less come into conflict, but that that harmony and concord should be preserved which is most akin to the foundations of both societies.
These, then, are the things taught by the Catholic Church concerning the constitution and government of the State. Concerning these sayings and decrees, if a man will only judge dispassionately, no form of Government is, per se, condemned as long as it has nothing repugnant to Catholic doctrine, and is able, if wisely and justly managed, to preserve the State in the best condition. Nor is it, per se, to be condemned whether the people have a greater or less share in the government; for at certain times and with the guarantee of certain laws, such participation may appertain, not only to the usefulness, but even to the duty of the citizens. Moreover, there is no just cause that any one should condemn the Church as being too restricted in gentleness, or inimical to that liberty which is natural and legitimate. In truth the Church judges it not lawful that the various kinds of Divine worship should have the same right as the true religion, still it does not therefore condemn those governors of States, who, for the sake of acquiring some great good, or preventing some great ill, patiently bear with manners and customs so that each kind of religion has its place in the State. Indeed the Church is wont diligently to take heed that no one be compelled against his will to embrace the Catholic Faith, for as Augustine wisely observes: "Credere non potest homo nisi volens." (Tract. xxvi., in Joan., n. 2.)
For a similar reason the Church cannot approve of that liberty which generates a contempt of the most sacred laws of God, and puts away the obedience due to legitimate power. For this is license rather than liberty, and is most correctly called by Augustine, "libertas perditionis" (Ep. cv., ad Donatistas. ii., n. 9); by the Apostle Peter, "a cloak for malice" (1 Peter ii. 16), indeed, since it is contrary to reason, it is a true servitude, for "Whosoever committeth sin is the servant of sin." (John viii. 34.) On the other hand, that liberty is natural and to be sought, which, if it be considered in relation to the individual, suffers not men to be the slaves of errors and evil desires, the worst of masters; if, in relation to the State, it presides wisely over the citizens, serves the faculty of augmenting public advantages, and defends the public interest from alien rule, this blameless liberty worthy of man the Church approves, above all, and has never ceased striving and contending to keep firm and whole among the people. In very truth, whatever things in the State chiefly avail for the common safety; whatever have been usefully instituted against the license of princes, consulting all the interests of the people; whatever forbid the governing authority to invade into municipal or domestic affairs; whatever avail to preserve the dignity and the character of man in preserving the equality of rights in individual citizens, of all these things the monuments of former ages witness the Catholic Church to have always been either the author, the promoter, or the guardian.