A Critique of John Locke’s Letter Concerning Toleration (Part III)

by Derek Remus

The following is the third and final part of a critique of John Locke’s Letter Concerning Toleration in the light of Catholic doctrine on the relation between Church and state. Part I was an exposition of Locke’s position. Part II summarized Catholic teaching on Church and state. It a slightly revised version of Derek Remus’s thesis at Thomas Aquinas College.
– The Editors

 III. The Godless State

It is now time to return to the Letter Concerning Toleration. In light of what we have said in the preceding section, let us reexamine Locke’s arguments for the thesis that the state has no care for souls and the Church has no interest in politics.

As we noted in our exposition of the Letter, Locke’s first two arguments for why the state can have no care of souls rely on the claim that, since the power of the state “consists only in outward force,” the state cannot exercise care of souls in any other way than by forcing its citizens to perform acts whereby they embrace the religion of the state. But force is incapable of affecting men’s mind and will, in which true religion really consists. Therefore, the state has no competence to force its citizens to embrace its religion. Therefore, it cannot have a care of souls.

The Catholic Church acknowledges that it is unjust for the state to force its citizens to perform acts whereby they become members of a given religion, even if that religion is the true one. Thus, the Church has always condemned forced baptisms. Nevertheless, there are ways for the state to make use of force in caring for souls which do not involve making its citizens perform acts whereby they become members of the true religion – in other words, ways other than forced baptism. The state in a nation where most people are Catholic, for example, can prohibit the erection of non-Catholic churches and the propagation of religious error in the press. In this way, it protects its Catholic citizens from dangers to their faith and thus, by fortifying that faith, can make its Catholic citizens more effective witnesses to the truth for its non-Catholic citizens. The state thus exercises care for the souls of both its Catholic and non-Catholic citizens, but it does not thereby force any unbaptized person to become a Catholic. Note, however, that since the Church is a perfect society with a real jurisdictional authority over its members, the Church has the authority to force baptized persons to remain faithful to their baptismal vows.[1] Moreover, in exercising this authority the Church has the right to use the temporal power (provided that those who exercise the temporal power are themselves baptized) as her agent.[2]

In general, Locke fails to distinguish between affecting the mind and will directly and affecting them indirectly. Only God can do the former, but men can do the latter, and one of the ways they can do it is through force. The state exemplifies this even apart from the question of religion, for the state by nature is interested in certain goods of the soul, namely, those which constitute political virtue, and can force its citizens to perform certain external acts that can dispose them internally toward the acquisition of these goods. To hold otherwise would be to deny the habituating power of law. All the more, then, is Locke wrong to equate care of souls with forcing men to embrace religions against their will.

Locke’s third argument for why the state cannot have a care of souls is that even if the compulsive power of the state could affect the interior dispositions of its citizens–something we have shown to be in some sense possible–, the “variety and contradiction” of the opinions of most princes with regard to religion would bring about the damnation rather than the salvation of most men, since most princes would force false religions on their subjects.

To say that the state has a care of souls and that it has a duty to worship God, however, is not to say that the state may adopt whatever religion it happens to like or even judges to be true. Rather, it is to say that the state has a duty to adopt the religion which has truly been revealed by God, namely, the Catholic religion. Therefore, if a ruler imposes a false religion on his subjects, he is in no way justified in doing so by the principle that the state has a care of souls. It is true that he may in fact impose a false religion on his subjects in the name of that principle, but the fact that a principle may be abused does not nullify the principle. Moreover, as Pope Leo XIII states, “it cannot be difficult to find out which is the true religion, if only it be sought with an earnest and unbiased mind; for proofs are abundant and striking.” He continues:

We have, for example, the fulfilment of prophecies, miracles in great numbers, the rapid spread of the faith in the midst of enemies and in face of overwhelming obstacles, the witness of the martyrs, and the like. From all these it is evident that the only true religion is the one established by Jesus Christ Himself, and which He committed to His Church to protect and to propagate.[3]

So much, then, for our reply to Locke’s third argument.

Locke’s fourth argument rests on the premises that the state exists for the sake of protecting its citizens’ “civil interests” alone and that the salvation or damnation of one’s fellow citizens in no way advances or harms one’s “civil interests.” A corollary of the latter premise is that the practice of whatever religion one happens to adopt is a natural right. Closely tied to this corollary is Locke’s view that the judgment of each individual is the supreme authority in matters of religion, a view which influences his definition of a church as a “voluntary society of men” who come together to worship God in the way that they see fit.

The view that the proper end of the state is the safeguarding of its citizens’ individual interests alone is simply a violation of the axiom that the common good is preferable to the private good. Underlying this violation is Locke’s view of man in the state of nature, where man comes into the world with the freedom to do whatever he wants with himself, provided that he does not hinder others from doing likewise. If this is so, then man’s chief good is to do whatever he wants, and therefore, his chief good is himself. Consequently, he has no natural end and cannot be perfected by pursuing some good extrinsic to himself. The law of nature, far from ordering man toward a determinate end, is merely a limit which prevents one complete whole from interfering with the activity of another complete whole. Hence, man cannot have a natural inclination for political life, nor can he be perfected by pursuing the good of a whole of which he forms a part, and so it is impossible for the state to come into being for the sake of anything other than the protection of goods that are purely individual.

The view that the salvation or damnation of one’s neighbor has nothing to do with one’s civil interests and that religion is therefore nothing more than the exercise of man’s natural right to liberty of conscience is also a violation of the axiom that the common good is preferable to the private good, since it makes religion, which is concerned with man’s highest end, a purely individual affair. Again, underlying this violation is Locke’s view of man in the state of nature. For if man’s natural status is that of an end in himself, then the nature of divine revelation must be such as to fit with the conditions of that status. This means that even if divine revelation enjoins duties on man’s conscience, from the standpoint of nature, man’s exercise of those duties is simply an exercise of his natural freedom to do whatever he likes, which includes, of course, following the dictates of his conscience. In this way, moreover, conscience derives its force simply from being an expression of the individual; in no way is that force related to the conformity of conscience to objective truth. Religion thus becomes something that concerns only the individual who practices it and is therefore a private good. Moreover, since neither the political nor the religious life of man demands ordination toward a common good as to its chief good, to argue, as we have done, that the good of the state is ordered toward the good of the Church as an inferior common good to a superior common good, is absurd.

From what we have said, it is clear that underpinning Locke’s rejection of the axiom that the common good is preferable to the private good is his rejection of man as ordered to an end. To respond adequately to this rejection, we would have to argue against Locke’s understanding of man as a knower. For as Locke makes clear in An Essay Concerning Human Understanding, all man can know are particular ideas received through sensation and reflection on the operations of his internal powers, together with the complex ideas that he himself composes from those simple ideas; therefore, he cannot know what things are universally, that is, he cannot know the natures of things. But if man cannot know the natures of things, it is futile to speak of him as being naturally ordered toward an end, and all that remains for him to pursue are the sensible pleasures that arise from his perception of sensible ideas. We shall simply take it as self-evident here that man can know the natures of things and that Locke is therefore wrong; to offer a dialectical argument by which to manifest man’s ability to know the natures of things would be beyond the scope of this thesis.

Man, then, is not an end in himself. The highest good of the state is a common good, not a collection of private goods. Religion is not a purely individual affair but one that demands participation in an ordered multitude which has as its object the most universal common good of all. Therefore, the good of the state is ordered toward the good of the Church as an inferior common good to a superior common good, and therefore, civil affairs are related to the salvation of souls.

Further, while it is true that the salvation of one’s neighbor does not affect one’s individual civil interests by agent causality, it may affect them by final causality. In other words, my neighbor can go to hell, and my money will still be intact; my possession of that money does not depend upon his salvation as on an agent cause. But his salvation may determine in some way how I ought to use my money; perhaps his faith is weak, and I ought to buy him a good religious book which God will use as a means for strengthening his faith. Therefore, the use of my money may depend upon my neighbor’s salvation as on a final cause. Therefore, the salvation or damnation of one’s neighbor can in some way affect even one’s individual civil interests.

Let us note, too, that liberty of conscience, as Locke understands it, implies a false notion of liberty. True liberty is the property of the will to choose those means appropriate to the end that reason apprehends as good. For since man is ordered toward an end, he must seek the means to attain it, and because he sees that these means “may exist or not,” insofar as they depend on the activity of his will, he is free to choose them.[4] Therefore, any act by which man defects from his true end is a defect from true liberty. This is so even if a man’s act is in accordance with the judgment of his reason but that judgment is false, since reason itself defects when it falls away from the truth. Hence, Locke’s conviction that man has a natural right to act in accordance with the dictates of his conscience, regardless of whether or not his conscience is conformed to truth, is false.

We have now responded to Locke’s arguments for why the state cannot have a care of souls. Further, since, as we saw in our exposition of A Letter Concerning Toleration, Locke’s arguments for why the Church can have no interest in political affairs depend on the same principles as his arguments for why the state cannot have a care of souls, we do not need to respond to the former arguments. There are, however, several other problems with Locke’s doctrine of the separation of Church and state that we should address.

First, to say that any two orders, such as the political and the ecclesiastical, have nothing to do with each other is opposed to the order of the universe. For God has ordained the universe to a single end, and therefore, the different orders within the universe stand in a determinate relation to each other. This would not be true, however, if certain orders in the universe are utterly irrelevant to each other.

Second, Locke’s separation of temporal from spiritual affairs is simply naïve. For even if religion orders man toward a good that is not of this world, it does the ordering in this world. Therefore, it must of necessity make certain stipulations about how man uses the things of this world. Consequently, the very nature of religion demands that there be such things as mixed matters, that is, matters which belong to both the temporal and spiritual orders and which fall within the jurisdiction of both the state and the Church. Therefore, the state and the Church cannot help but interact with each other, if religion is to be anything real at all in the world.

Third, in Locke’s doctrine of separation of Church and state, a church is defined as “a voluntary society of men, joining themselves together of their own accord in order to the public worshipping of God in such manner as they judge acceptable to Him, and effectual to the salvation of their souls.” This definition, however, in effect reduces the church to a purely human institution. The state must, of course, subscribe to this definition. The position that all churches are purely human institutions, however, is just as much a judgment about religion as the position that one Church is not of purely human origin. Therefore, the separation of Church and state itself demands that the state make judgments about religious matters.

Fourth, despite his reduction of religious practice to the level of a natural right, i.e. a determination of man’s natural “state of perfect freedom,” Locke holds that there is such a thing as divine revelation and that “the observance of these things [prescribed by divine revelation] is the highest obligation that lies upon mankind.”[5] This is to say that from the standpoint of nature, the practice of religion is an exercise of man’s freedom to do with himself whatever he wants, but from the standpoint of what is above nature, the practice of religion is a duty which restricts man’s freedom to do with himself whatever he wants. This is in effect to introduce an opposition between the natural and the supernatural orders. Such an opposition is, of course, absurd, since God is the source of both orders, and grace does not destroy nature but presupposes and perfects it.[6]

Fifth, the separation of Church and state is ultimately a rejection of God. For to say that the state must treat all religions equally is to say that the state must be indifferent to whether any of those religions has been instituted by God. But to say that the state must be indifferent to whether any of those religions has been instituted by God is to say that the state has no duty to worship God. To say that the state has no duty to worship God is to say that the state in no way depends upon God.

A deadly practical consequence follows from the proposition that the state does not depend upon God, namely, the independence of the state from the dictates of the natural law. We have seen that the natural law is simply the participation of the rational creature in the eternal law; therefore, to deny the eternal law is to deny the natural law. But to hold that the state does not depend upon God is in effect to deny the eternal law, since it is to deny that the state is a secondary cause within a plan by which God governs the universe.   Therefore, it follows from the doctrine of the separation of Church and state that the law of the state in no way depends upon the natural law for its legitimacy. The state may therefore do whatever it pleases; it has no obligation to serve the common good of its citizens but is like a big individual to whose private good the goods of its citizens are subservient.

Locke himself, of course, holds that there is a God and even that the state should not tolerate atheism, inasmuch as “[p]romises, covenants, and oaths, which are the bonds of human society, can have no hold upon an atheist.”[7] Locke’s reason for holding the latter thesis, however, is not because of any actual duty of the state towards God but merely because of the practical necessity of believing in God for the sake of civil stability. Yet does a state which considers itself under no obligation to maintain the good of its citizens really need to promote belief in God for the sake of what it considers as civil stability? Could such a state not effect its own vision of stability by means of sheer force or, even better, by giving its citizens an abundance of sensual pleasure to keep them happy? It does not take much reflection to see that this is the kind of state that exists in most countries of the Western world today. Let this suffice for our refutation of the Lockean doctrine of the separation of Church and state.


In sum, a consideration of the true nature and purpose of the state and the Church, in light of the axiom of the primacy of the common good, leads us to the conclusion that the Catholic Church is right about the relations between Church and state. After the coming of Christ, the state has a duty to publicly profess the Catholic religion and, in the words of St. Thomas, “to procure the good life of the multitude according as it agrees for pursuing celestial beatitude.”[8] The Church, for its part, has the right to ensure, as far as it has the power, that the state fulfills these duties.

On the other hand, Locke’s contention that the state should treat all religions within its domain equally and that the Church should stay out of politics stems from a false understanding of the nature and purpose of the state and the Church, an understanding which arises from his exaltation of the private good above the common good.

A correct understanding of the principles governing the relations between the Church and the state is critical in our day, when the individualism and religious indifferentism of the doctrine of separation of Church and state have become a matter of intellectual custom for most people. If a society cannot really flourish unless it acknowledges God, then so long as the truth about Church and state is not recognized and men refuse to acknowledge that Christ is king not only of individuals but of nations, the world will not be rid of its many evils and will never attain true peace. But wherever that truth is recognized and men do acknowledge that Christ is king of the nations, the state will attain true political happiness, the Church will be able to exercise her mission fully, and men will enjoy happily the passing goods of life on earth as they strive with good hope to attain the eternal good of life in heaven.

Having read the account of the relations between Church and state given above, one may very likely ask: is not such an account absurd given the conditions of the modern world, where numerous countries, such as the United States, contain large portions of non-Catholics and are characterized by that great achievement of contemporary man called religious pluralism? To answer this question, let us begin by acknowledging that in many countries today the realization of the principles that we have articulated concerning the Church and the state is practically impossible. Therefore, it would not be prudent for the Church to insist that the governments of such countries fulfill the duties imposed on them by those principles in all their fullness. That, however, does not negate the truth of those principles, which are based upon the very nature of the Church and the state. No particular difficulty in implementing them can undermine their universal validity as an element of the objectively right order of things. The following quotation from Pope Leo XIII in his Encyclical Longinqua (On Catholicism in the United States) testifies to the absolute validity of the said principles even for a country like the United States:

“[T]he Church amongst you, unopposed by the Constitution and government of your nation, fettered by no hostile legislation, protected against violence by the common laws and the impartiality of the tribunals, is free to live and act without hindrance. Yet, though all this is true, it would be very erroneous to draw the conclusion that in America is to be sought the type of the most desirable status of the Church, or that it would be universally lawful or expedient for State and Church to be, as in America, dissevered and divorced. The fact that Catholicity with you is in good condition, nay, is even enjoying a prosperous growth, is by all means to be attributed to the fecundity with which God has endowed His Church, in virtue of which unless men or circumstances interfere, she spontaneously expands and propagates herself; but she would bring forth more abundant fruits if, in addition to liberty, she enjoyed the favor of the laws and the patronage of the public authority.”[9]

Moreover, as we have seen, a government which holds in principle that it must treat all religions within its domain equally and that those religions must in turn refrain from any intervention in politics cannot tolerate the Catholic Church and be consistent with itself. Nor can it acknowledge its duty to ensure that its laws are in accordance with the natural law. Such a government may not realize these consequences of the doctrine of separation of Church and state at first, but after a period of time, during which it is able to develop its understanding of that doctrine, it is virtually impossible that it will not realize them. The promotion by the state of numerous forms of immorality in the United States, Canada, and several European nations, together with the more and more frequent clashes between the Catholic Church and the governments of those nations over matters such as abortion and homosexual “marriage,” testifies to this. Therefore, even if it is unreasonable to expect that the governments of nations with large non-Catholic populations will recognize the Catholic Church as the true religion and the infallible interpreter of the moral law, the Catholic Church will inevitably end up suffering persecution in those nations, and the natural law will end up being abandoned.

Consequently, even in countries where it is imprudent for the Church to demand the realization of the right order governing the relations between Church and state in all its fullness, Catholics cannot feel satisfied with the lack of that realization. Therefore, they must strive to win as many non-Catholics to the Church as possible and must work to establish the proper natural basis for the right relations between Church and state by instilling in men’s minds the primacy of the common good and the foundation of the state in natural law. In this way, Catholics in non-Catholic countries will do what they can to peacefully pave the way for the time when the fullness of the right order can be realized.


[1] Of course, by defining a church as a mere “voluntary society of men,” Locke strips the Catholic Church of her status as a perfect society and therefore of all real jurisdictional power. I shall discuss Locke’s definition of “church” at greater length further on.

[2] For a more detailed account of the Church’s right to coerce the baptized to keep their baptismal promises, as well as her right to make use of the temporal power in doing so, see Pater Edmund Waldstein, “Religious Liberty and Tradition,” The Josias, https://thejosias.com/2014/12/31/religious-liberty-and-tradition-i/).

[3]       Immortale Dei, n. 7.

[4]       Pope Leo XIII, Libertas (On the Nature of Human Liberty), nos. 5 and 6.

[5]       Letter, p. 15.

[6]       Cf. Summa, Ia, q. 2, a. 2, ad primum: “…sic enim fides praesupponit cognitionem naturalem, sicut gratia naturam, et ut perfectio perfectibile.”

[7]       Ibid., p. 18.

[8]       De Regno, Liber 1, Caput 16: “Quia igitur vitae, qua in praesenti bene vivimus, finis est beatitudo caelestis, ad regis officium pertinet ea ratione vitam multitudinis bonam procurare secundum quod congruit ad caelestem beatitudinem consequendam.”

[9]       Pope Leo XIII, Longinqua (On Catholicism in the United States), n. 6.