Some time ago, I wrote an essay claiming St. Thomas as the first Whig, one of the founders of “the party of liberty.” One antecedent to this claim comes in the essays of Lord Acton on the origins of the idea of liberty, and other antecedents in the political writings of Jacques Maritain, Thomas Gilby, and John Courtney Murray. Basic concepts analyzed by St. Thomas—concepts of the human person, conscience, liberty, the source of political power in the people, and the twin principles of the consent of the governed and the “mixed regime”—provided rich soil for the free institutions that were to arise much later in history.

To all this, however, there is one exception, although a very large one. Among serious thinkers in America who are hostile to Catholicism, Article 3 of Question 11 in the Secunda Secundae has probably been more frequently cited than any other paragraph in the entire collected works of St. Thomas Aquinas. The subject of this article is, Are heretics to be tolerated?, to which Aquinas replies, in brief, No. How on earth could Aquinas justify such a shocking judgment?

The answer Thomas gave did not, of course, shock his contemporaries. But that fact does not exonerate him. On the contrary, it reinforces the views of those who believe that Catholic teaching is inherently intolerant, by handing them evidence that the Catholic culture of the thirteenth century was narrow-minded, cold-blooded, and cruel.

Some background is in order. When Thomas Aquinas was thirteen or so, the Benedictine Monastery of Monte Cassino, where he was a boarding student and oblate, was put to fire and sword by cavalry of Frederick II, the proud and defiant German Emperor. Eleven monks were run through and burned to death. This was the monastery over which the Aquino family—and even the pope—had realistic hopes of making Thomas abbot. The young Thomas was sent home for a year, and later enrolled at the new University of Naples, where he encountered the newly founded Order of Preachers.

A few years later, Frederick II was excommunicated by the Council of Lyons, purportedly for the reign of massacre and terror that he had inflicted upon cities throughout Italy. Frederick was capable at a whim of ordering an entire city razed, its men butchered or sold into slavery, its women sent eastward to become slaves of his Saracen friends. Frederick considered himself duty-bound to protect and to extend the patrimony of his family, the Hohenstaufens. He was in almost constant conflict with the popes, mostly for territorial and worldly reasons, although his personal habits and deeds also made him vulnerable to censure on spiritual grounds. And yet his most recent biographer, David Abulafia (Frederick II: A Medieval Emperor, 1988), shows considerable evidence that Frederick—despite being condemned by some (and praised by others) for being the scourge of the papacy—wished to remain by his own lights an orthodox if rather eccentric Catholic. Frederick II remains an ambiguous figure who has haunted the German imagination even into our own century.

After Frederick’s excommunication at Lyons, the two older brothers of Thomas Aquinas, who had served in Frederick’s court for decades, joined in a rebellion against Frederick at Parma that eventually failed, but not without coming close to success. When the rebellion’s leader, the elderly Baron San Severino, was finally captured, Frederick ordered the seventy-year-old’s nose cut off, tongue cut out, and one leg hacked off, and then commanded that he be carted in rags from village to village, so that Italians could see for themselves the price of rebellion. San Severino was the father-in-law of St. Thomas’ younger sister, Theodora. The two brothers of Aquinas, former courtiers of Frederick, were tortured, made to languish in prison for years, and at last executed.

Frederick II was held by many to be the Great Heretic of the epoch, who for nearly thirty years waged constant warfare throughout Italy, leaving a train of ruin, slaughter, humiliation, and misery. Just as St. Thomas was fortunate to know personally one king who was widely regarded as a saint, Louis IX of France, and at least two who were, on the whole, good kings, Edward Plantagenet of England and Charles of Anjou, so he knew through bloody experience a king who was—and rejoiced in being—an on-again, off-again foe of popes. When the term “heretic” was used, it was not for Thomas Aquinas or his contemporaries an abstraction.

Nevertheless, Frederick II was himself a foe of heresy. In his own legal code promulgated at Melfi in 1231, Frederick followed the legal precedents of the era, including those of the Fourth Lateran Council of 1215, in condemning heresy, sacrilege, treason, usury, and counterfeiting (in that order) as structural crimes against the state. Professor Abulafia, himself no admirer of the Church of Frederick’s time, explains the rationale of the Melfi code:

Heresy, indeed, is presented as treason. Those who deny the articles of the Catholic faith implicitly deny the claims of rulers to derive their authority from God. They are enemies not merely of God and of the souls of individuals, but of the social fabric. Their questioning of religious truth involves a questioning of the monarch’s command over the law; as enemies of the law, they are its legitimate targets, and the position of primacy accorded to legislation against heretics is thus entirely proper.

The growing preoccupation with heresy in the thirteenth century, as became apparent at the Lateran Council, seems to have been partly due to the scandals that accompanied the wealth and political power of the medieval papacy. The vivid contrast between the evangelical witness to poverty and charity and the grandiosity of the papal court stirred many popular passions. The constant warfare, heavy taxation, and depredations of battle that the poor were obliged to endure for generation after generation threw thousands into misery and discontent.



Meanwhile, the thinking of the ordinary people (as well as many of the learned) remained tinged with Platonism and Manicheanism, as it had been for centuries. In a pre-Christian manner, people tended to believe that the essential conflict in the human soul is the battle between the flesh and the spirit. Sometimes they inflated this battle to such grand dimensions that for them the world was divided between two cosmic forces, good and evil. From this it was a short step to declaring that everything connected with the human body is evil, and that in a “higher,” purely spiritual state of consciousness lay the only human good. Such views had been common in gnostic circles for centuries.

Corollaries to these notions were that embodied human beings are intrinsically evil and must undertake severe ascetical practices to “free” the soul from its carnal prison; that marriage and the getting of children is evil; and that the Catholic Church, with its bodily sacraments and its doctrines of “the resurrection of the flesh,” not to mention its rich and worldly ways, is a principle of evil. Holding such beliefs, a significant body of citizens in Northern Italy and Southern France “cut” themselves off (sectare) from the Catholic consensus, and began to form churches, even dioceses, of their own. These “sects” came to be called Cathari (the Pure Ones) or Albigensians, and came to be seen as radical threats not only to the moral and religious order but even to the political order of the time. Against them popes and kings launched local crusades, just as they had against the distant Saracen occupiers of the Holy Lands.

It is likely that the term “heretics” in the writings of St. Thomas referred to these sectarians most of all. Indeed, the founding of the Order of Preachers in Toulouse in Southern France immediately involved St. Dominic and his colleagues in preaching against the Cathari throughout the region. At a time when the doctrines of Joachim of Fiore (1135-1202) were rapidly spreading, the poor were especially vulnerable to the millenarianism of the Cathari, their attacks on the riches of the Church and the worldliness of kings, and their evocations of poverty and contempt for the body. By assuming themselves a life of evangelical poverty, combined with orthodox preaching about the goodness of creation and the human body, the Dominicans undercut the preaching of the Cathari. The Dominicans and the Franciscans sponsored the first creches, which were becoming popular at this time, offering tender scenes of the birth of Jesus in the crib at Bethlehem. They wished to bring out the human, fleshly side of Christianity.

The Cathari, in effect, forced the Catholic community to distinguish itself far more sharply than before from Platonism and Manicheanism. The body-affirming, incarnate side of Christian teaching, combined with a reawakening of the aspiration toward a life of evangelical poverty, came to vivid life in the preaching of St. Dominic and also of St. Francis of Assisi (1182-1226), notably in his hymns to the goodness of birds, animals, and all the earth.

At the same time, the philosophy of Aristotle was also beginning to reach the Christian world of the thirteenth century, correcting the philosophy of Plato on the place of the body, earth, empiricism, time, and contingency in human life. The clarity of Aristotle, however, was clouded by the Platonic preferences of the Islamic commentators, especially Avicenna and Averroes, through whom the newly discovered texts of Aristotle—missing from the West for a millennium—were becoming known. In universities from Naples and Bologna to Paris and Oxford, secular masters opposed to the religious orders and to the constraints of the existing Christian order gladly embraced these Arabian glosses on Aristotle.

These glosses called into question the creation of the world in time, the role of the senses and the imagination in human knowing, the individuality (and personal responsibility) of the human intellect and will, the immortality of the human composite of body and soul, the role of divine Providence, the simple standard of one truth governing both theology and philosophy, and other foundations of both Catholic faith and empirical (as distinct from gnostic) reason. Among Scholastic philosophers themselves, Platonists and such Averroists as the brilliant Siger of Brabant championed these doctrines, sometimes in full recognition of the devastation they wrought in Christian teaching, sometimes blindly.

Thus, in the thirteenth century, within the bosom of Christianity and in the heart of the Christian universities themselves, the intellectual stakes were very high. Small mistakes in philosophy (concerning the role of the senses in cognition, for example) led inexorably to the denial of basic foundations of the Christian faith. In such heady, fertile, creative times, moreover, pride in one’s own intellectual originality was an ever-present intoxicant. Truth was often intermixed with falsehood, good with evil. The art of discernment was a vital necessity, both in the arena of theory and in the arena of practice. The Catholic world felt in these new times an urgent need for a sensus Christi, a way of thinking in, through, and with the revelation of Jesus Christ, the Logos “through Whom and with Whom and in Whom were made all the things that are made.”

This is the context within which St. Albert the Great discovered in his pupil Thomas a rare equanimity of spirit and a fearless intellect, and saw in this tall, large-framed lad, regarded by his fellow students as a speechless ox, “an ox whose bellows will be heard around the world.” Aquinas took to the insights of Aristotle into the relations of body and spirit as a fish to water. He seized upon these (not least in his tractatus Against the Averroists: On There Being Only One Intellect) as a key for shedding crucial light on aspects of Christian doctrine much threatened by the Cathari, on the one hand, and by the Averroists, on the other.

Aquinas saw, of course, that Aristotle was not always right, and did not hesitate to correct him, to push his thought further (to original notions of the conscience and the will, for instance), and above all to build an entirely new context—that of the revelation of love in Jesus Christ—for understanding even the things Aristotle got right. In brief, Albert the Great, the most learned man of his time, saw in his pupil the new master of the Christian inheritance to that time. That brief era itself had its own faults, and the Thomistic synthesis would itself contain damaging weaknesses.

Thomas begins Article 3 of Question 11 by citing three traditional texts. The first of these texts urges forbearance and gentleness; the second declares the necessity for factions in the Church in order that “those who are genuine among you may be recognized”; and the third cites the parable that the servant should suffer the tares to grow along with the wheat until the end of time. After repeating these traditional texts, St. Thomas turns sharply against the heretic. Let me quote him in full, because the text runs so directly against contemporary sensibilities and understandings.

With regard to heretics there are two points to be observed, one on their side, the other on the side of the Church. As for heretics their sin deserves banishment, not only from the Church by excommunication, but also from this world by death. To corrupt the faith, whereby the soul lives, is much graver than to counterfeit money, which supports temporal life. Since forgers and other malefactors are summarily condemned to death by the civil authorities, with much more reason may heretics as soon as they are convicted of heresy be not only excommunicated, but also justly be put to death.



But on the side of the Church is mercy which seeks the conversion of the wanderer, and She condemns him not at once, but after the first and second admonition, as the Apostle directs. Afterwards, however, if he is still stubborn, the Church takes care of the salvation of others by separating him from the Church through excommunication, and delivers him to the secular court to be removed from this world by death. The Decretum repeats Jerome’s comment, Cut off the decayed flesh, expel the mangy sheep from the fold, lest the whole house . . . the whole body, the whole flock burn, perish, rot, die. Arius was but a single spark in Alexandria, but as it was not at once put out, the whole world was laid waste by his flame.

To read this text, we must clarify what Aquinas means by heretic. He does not mean a Muslim or a Jew, an unbeliever or an infidel. He means a Catholic who has chosen to deny his faith, in whole or in part. For Jews and Muslims, Aquinas argues for toleration, not only of their persons but also of their public rites. It is true that from his viewpoint their faiths are incomplete and to that extent erroneous. It is also true that for Thomas toleration is a means for gaining respect for the true faith, rather than an end in itself, a duty simply owed to the conscience of others. But he does argue for toleration for Jews and Muslims in an emphatic way, as he does not for heretics. About the Jews, for example, he writes: “Among unbelievers there are some who have never received the faith, such as heathens and Jews. These are by no means to be compelled, for belief is voluntary.” And about the religious rites of Jews and Muslims, he adds:

just from the fact that the Jews keep their ceremonies, which once foreshadowed the truth of the faith we now hold, there follows this good, that our very enemies bear witness to our faith, and that what we believe is set forth as in a figure. The rites of other infidels, which bear no truth or profit, are not to be tolerated in the same way, except perhaps to avoid some evil, for instance the scandal or disturbance that might result, or the hindrance to the salvation of those who, were they unmolested, might gradually be converted to the faith.

Similarly, Aquinas shows a great deal more respect for unbelievers, such as his beloved Aristotle, who knew nothing whatever about Christ and His revelation than he does for heretics. He admires in unbelievers how much of the truth about man revealed by Christ they had come to simply by studying the laws of their own being. (For Aquinas, it is inconceivable that there are two truths, one learned from the things that are, the other learned from faith. For him, the one God, the Creator, is the sole source of truth.) For that he respects them, acknowledging that by fidelity to truth they served the God they did not know, and so are dear to God.

The student of Aquinas already familiar with his teachings on individual personal responsibility, conscience, and the role of reason and will in free choice is likely to be surprised by his unremitting hostility to heretics. In a typical passage, Thomas wrote:

Every judgment of conscience, be it right or wrong, be it about things evil in themselves or morally indifferent, is obligatory, in such wise that he who acts against his conscience always sins.

Or again, this passage from the Summa Theologica:

Since conscience is the dictate of reason, the application of theory to practice, the inquiry, whether a will that disobeys an erroneous conscience is right, is the same as, whether a man is obliged to follow a mistaken conscience. Now because the object of a volition is that which is proposed by the reason, if the will chooses to do what the reason considers to be wrong, then the will goes out to it in the guise of evil. Therefore it must be said flatly that the will which disobeys the reason, whether true or mistaken, is always in the wrong.

Given such teachings as these, why could not Thomas respect the conscience of heretics?

By heretic, again, Aquinas meant a person of Catholic faith who deliberately and resolutely, even after having been called to reflect on the matter, has chosen to renounce that faith in some important particular. Aquinas points out that the word heresy comes from the Greek word for choice. Heresy for him is not a mistake of the intellect but a choice of the will. It is a choice of adherence to a proposition, or set of propositions, known by the chooser to contradict the Catholic faith. It is a choice to cut oneself off from communion in the Catholic faith, to put oneself in a sect—a thing cut off. It is right, insists Aquinas, that such choice be dealt with harshly.

But what about the thousands throughout France and Italy and Spain falsely accused of heresy, or wrongly caught up in the machinery of heresy-hunting? Cloistered Aquinas might be, but he could hardly have helped knowing at least a little about the role that some Dominicans of his day were playing in the inquisition of heretics.

In the thirteenth century, all sorts of cruelties were common. The popes themselves committed ten of nineteen descendants of Frederick II to prison, one of his daughters for forty-eight years, and saw to the deaths of others in battle or capture. When Frederick II’s chief advisor, Taddeo da Suessy, was taken prisoner at Parma, his hands were immediately cut off by those loyal to the pope and he was thrown into a dungeon. For suspicion of stealing from him, Frederick seized his other chief advisor, the poet della Vigna (later celebrated by Dante), had his eyes burned out, and threw him into a dungeon. There the poet killed himself by pounding his head against the damp stone walls. In southern France, men and women alike were accused of being heretics, given no way to defend themselves except by enduring torture, and if found guilty covered with pitch and set aflame. Swords aloft, soldiers were set free upon entire settlements of heretics, which they torched. During the lifetime of Aquinas, all of Provence was swept by violence against heretics-some of whom were living, according to their own lights, admirable evangelical lives.

Yet the cold words of Aquinas stand there, approving of the use of the secular arm, describing heresy as a pestilence to be blotted out, diseased cells to be cut away. And Aquinas concludes with the terrible ruthlessness of the words of St. Jerome: Arius and the sons of Arius should be extinguished before their contagion spreads. How could the medievals—even such defenders of conscience as Aquinas—think this way? Before we judge them (by our modern lights) guilty of “heresy,” we should at least try to understand why their reasoning seemed to them persuasive.

As we have seen in the case of Frederick II, the reasons that kings and emperors, even those at war with the papacy, listed heresy first among the crimes against the state were several and profound. For one thing, kings claimed power from God according to the Christian faith and, often enough, especially in that age of exaggerated papal claims to universal worldly power, their power was tangibly and visibly legitimated directly through coronation by the pope of Rome. Heresy directly undercut kingly power.

For another thing, thirteenth-century societies were highly fragile. Beyond ties of kinship, many citizens experienced little to bind them to others. Most were subjects of a few—and one ruling aristocrat was often overturned by another. Sharing in the local horizons of small cities or villages might bond people in intimate memories, and participating in guilds or trades might offer some association outside of family or neighborhood life. But geographical isolation was often intense, and shifting patterns of warfare, baronial allegiance, and foreign occupation awakened acute local insecurity. Under political anarchy, the common people and the poor suffered much. Under all these uncertainties, the chief consensual bond among people was Catholic faith and Catholic ritual. Virtually all unifying conceptions of relationship and social weight, meaning and order, came from that faith.

Neither the rich nor the nobility (increasingly, as trade and commerce grew, these were not necessarily the same) could trust one another. Barons and counts were obliged to protect themselves against each other by dwelling within heavily armed fortresses. (Even the Aquino family had three castles, with knights sufficient to defend them; the novelist Louis de Wohl imagines that the Aquinos could bring one hundred knights to the service of the Emperor.) An immediate and common form of justice was the vendetta. The politics even of princes was first and chiefly about naked power, and princes were thrown back upon shifting alliances based upon self-interest. The struggle to build national, let alone international, systems of justice, reason, and legality was still in its infancy.

On the other hand, in the no-man’s-land between warring barons and ordinary people, lay confraternities were beginning to spring up to fill the looming social vacuum by undertaking needed civic projects. A new class of lay professionals led by trailblazers such as Albertanus of Brescia was setting the foundations of a civic order. But the emergence of a true civil society lay far in the future. In the thirteenth century, there still seemed to be something like the war of all against all. Emperors, kings, barons, counts, and even bishops and popes seemed to be in perpetual strife with one another.

The time was not yet ripe for the impulses of modernity, or even for the reformation of the Church. The precariousness of life, under threat from famine and plague as well as from war, was signalled in the apocalyptic feelings and expressions of the time. The still greater precariousness of civilization, now barely emerging from centuries of illiterate tribal barbarism, was widely felt. Monastery schools and libraries, professional schools and universities, were still relatively new institutions frequented only by a few.

This was the context within which, no matter how horrendous the measures being practiced to keep it in check, heresy was perceived as the primal threat to social order, both by ecclesiastics and by secular rulers. What Thomas Aquinas argued against heretics had already been codified in both civil and ecclesiastical law for at least two generations. One might have hoped that many of Thomas’ own principles about the human person, liberty, conscience, and the indispensable freedom of faith would have led him to oppose the widespread legal consensus. Perhaps, though, an even greater moral and civil anarchy would have resulted than people were then already experiencing. Perhaps their sense of precariousness was already stretched beyond human tolerance.

Narrow and constricted as it was, the order supplied to the European peoples by primitive Christendom, that premature construction of a supposed City of God on earth, may have seemed better than the chaos of a war of all against all. Bad as it was, an enforced consensus in the faith, at least among those who had once accepted it, seemed to most at the time better than the alternative.

It would not always be so. The Protestant Reformation was looming only two centuries ahead. But by then civic institutions, commerce, prosperity, literacy, and many other fundamentals of a new order would be much farther advanced.

It is easy to see how many Christians of patristic and medieval times could have thought that the City of God imagined by St. Augustine required a system in which cult would be the center of culture. It is not even too hard to understand how the primacy of the spiritual power revealed by Jesus Christ, by comparison with the secular power, might be thought to require official, public recognition of the primacy of the Church. From that, it would be a small step to the claims of Innocent III that the secular power was subordinate to the spiritual power, so that the pope deserved primacy over all merely secular powers. The logic of how such ideas developed is clear.

But the unintended consequences of such conceptions were many—and often damaging to Church and society alike. Perhaps, as we have noted, it was necessary and even useful in the actual flow of history for the Church, and especially the papacy, to step into the vacuum left by the collapse of the Roman Empire in Europe and the Middle East. In any case, that is what happened. Unless it had happened, it is hard to see what other institution would have inspired and actually accomplished the building of the libraries, universities, and schools that sponsored the study of the great treasures of Greece and Rome and the new discoveries of later centuries. Apart from the guardianship of the Church over many centuries, it is hard to see whence would have derived the resources that later gave rise to modern science, the Renaissance, and the Enlightenment. The fundamental conceptions of progress, truth, compassion, the dignity of the individual, and the centrality of personal liberty on which modern progress rests are rooted in Jewish and Christian beliefs about human nature and destiny.

Nonetheless, the costs of the Church’s trusteeship were high. In placing the guardianship of the consensual ideals of worldly civilization in the hands of the Christian Church, the Christian West wound up violating consciences and putting heretics to death in abominable ways. However divinely protected the human institutions of the Church may be, they are bound to be weighed down in daily practice by human frailty and sin. And protests against frailty and sin—against corruptions and abuses—can conveniently be interpreted as heresy. Once the integrity of the social fabric had been made to rest on key Christian beliefs (and the power of legitimate rulers on ecclesiastical approbation), criticisms of Christian practice that spilled over into criticism of underlying interpretations of the gospels were easily taken as acts of treason against the state.

In short, by allowing Christian faith to be the consensual foundation of the political and social order, as it were the form of political life, Christendom confounded the things of Caesar with the things of God. In modern times, such a vision, at least in analogous if not precisely the same form, has been called “integrism.” Integrism is a premature uniting of the institutions of faith and the institutions of the state. (I do not say the institutions of church and state, but those of faith and state, since the latter is an even more profound temptation than the former.)

The Christendom of the thirteenth century understood itself as having as its foundational form the integrity of Christian faith. For this reason, it was bound to reject heresy as treason to the state. The state could tolerate those who did not pretend to be Christian, for Christian teachings themselves commended such toleration (and actually more than that, a genuine respect for good-faith differences of conscience). What it could not tolerate was those of counterfeit faith, those who said they were Christians while choosing to deny important aspects of Christian faith. For the likelihood of many persons at once launching diverse interpretations of the gospels and organizing themselves in rival organizations, and thus undermining the foundations of the monistic state, was extremely high, as Europe was to experience in centuries after the thirteenth.

At the close of the twentieth century, it cannot be said that we have yet solved the problem of the proper relation between the Christian faith and the state. (The Jewish state of Israel and the Muslim states have not solved this problem either, nor have the forces of secular humanism proven any more adept at addressing the moral and cultural crisis of modern societies.) As the great French social philosopher Pierre Manent has pointed out, the modern secular nation state is itself in a crisis of transition; and the Catholic Church, having made its peace with and given its support to democratic experiments, is necessarily concerned with a corrosive “privatizing” and relativizing of conscience.

It is obvious that the interests of Thomas Aquinas were metaphysical and theological rather than social or political. His treatment of questions regarding the former sparkle with originality; his treatments of the latter are, for the most part, perfunctory. But for those of us who work in political and social philosophy (and theology), a great question remains: What is the proper relation of Christian faith to the open society? A relation that entails the persecution of heretics is clearly repugnant to Christian faith. The special circumstances of the thirteenth century remain a vivid case study in what not to do. But if the profession of Christian faith is not to be constitutionally required, as certainly it should not be, just how can Christian faith escape from being merely privatized and relativized? And how can open societies themselves be saved from giving a posthumous victory to such relativists as Hitler and Mussolini, who began by stating that nothing in politics is right or wrong, that only power matters?

Such problems have not received resolution in our own time. Perhaps they can never be resolved with finality, but solely by trial and error, and on an always tentative basis.

Michael Novak holds the George Frederick Jewett Chair in Religion and Public Policy at the American Enterprise Institute.