Catholics and Protestants united in approving the sentence. The Inquisition at Vienne, cheated of its living prey, burned Servetus in effigy. Melanchthon, in a letter to Calvin and Bullinger, gave “thanks to the Son of God” for the “punishment of this blasphemous man,” and called the burning “a pious and memorable example to all posterity.”73 Bucer declared from his pulpit in Strasbourg that Servetus had deserved to be disemboweled and torn to pieces.74 Bullinger, generally humane, agreed that civil magistrates must punish blasphemy with death.75

Yet even in Calvin’s day some voices spoke for Servetus. A Sicilian wrote a long poem, De iniusto Serveti incendio. David Joris of Basel, an Anabaptist, published a protest against the execution, but under a pseudonymn; after his death his authorship was discovered; his body was exhumed and publicly burned (1566). The political opponents of Calvin naturally condemned his treatment of Servetus, and some of his friends deprecated the severity of the sentence as encouraging the Catholics of France to apply the death penalty to Huguenots. Such criticism must have been widespread, for in February 1554, Calvin issued a Defensio orthodoxae fidei de sacra Trinitate contra prodigiosos errores Michaelis Serveti. If, he argued, we believe in the inspiration of the Bible, then we know the truth, and all who oppose it are enemies and blasphemers of God. Since their offense is immeasurably greater than any other crime, the civil authority must punish heretics as worse than murderers; for murder merely kills the body, while heresy accepted damns the soul to everlasting hell. (This was precisely the Catholic position.) Moreover, God Himself has explicitly instructed us to kill heretics, to smite with the sword any city that abandons the worship of the true faith revealed by Him. Calvin quoted the ferocious decrees of Deut. 13:5–15, 17:2–5; Exodus 22:20; and Lev. 24:16, and argued from them with truly burning eloquence:

Whoever shall maintain that wrong is done to heretics and blasphemers in punishing them makes himself an accomplice in their crime.... There is no question here of man’s authority; it is God Who speaks, and it is clear what law He would have kept in the Church even to the end of the world. Wherefore does He demand of us so extreme severity if not to show us that due honor is not paid Him so long as we set not His service above every human consideration, so that we spare not kin nor blood of any, and forget all humanity when the matter is to combat for His glory? 76

Calvin moderated his conclusions by counseling mercy to those whose heresies were not fundamental, or were clearly due to ignorance or feebleness of mind. But whereas in general he accepted St. Paul as his guide, he refused to use the Pauline expedient of declaring the old law superseded by the new. In truth the theocracy that he had apparently established would have crumbled into disorder if differences of creed had been allowed public voice.

What, meanwhile, had become of the Erasmian spirit of tolerance? Erasmus had been tolerant because he had not been certain; Luther and Melanchthon had abandoned tolerance as they progressed in certainty; Calvin, with lethal precocity, had been certain almost from his twentieth year. A few humanists who had studied classic thought, and had not been frightened back into the Roman fold by distaste for the violence of theological strife, remained to suggest, diffidently, that certainty in religion and philosophy is unattainable, and that therefore theologians and philosophers should not kill.

The humanist who most clearly spoke for tolerance amid the clash of certainties had been for a time one of Calvin’s closest friends. Sebastian Castellio, born in the French Jura in 1515, became an adept in Latin, Greek, and Hebrew, taught Greek at Lyons, lived with Calvin in Strasbourg, was appointed by him rector of the Latin School at Geneva (1541), and began there a translation of the entire Bible into Ciceronian Latin. While he admired Calvin as a man, he abominated the doctrine of predestination, and fretted under the new discipline of body and mind. In 1544 he charged the Genevese ministers with intolerance, impurity, and drunkenness. Calvin complained to the Council; Castellio was found guilty of calumny, and was banished (1544). For nine years he lived in great poverty, supporting a large family, and working at night on his version of the Scriptures. He finished this in 1551; then, lonesome for the placid drudgery of scholarship, he began again at Genesis 1:1, and translated the Bible into French. Finally (1553) he obtained a professorship of Greek at the University of Basel. He sympathized with the Unitarians, longed to help Servetus, and was shocked by Calvin’s defense of the execution. Under assumed names he and Caelius Curio published (March 1554) the first modern classic on toleration: De haereticis an sint persequendi (Should Heretics Be Persecuted?)

The main body of the work was an anthology, compiled by Curio, of Christian pleas for tolerance, from Lactantius and Jerome to Erasmus, the early Luther, and Calvin himself. Castellio contributed the argument in preface and epilogue. For hundreds of years, he pointed out, men had debated free will, predestination, heaven and hell, Christ and the Trinity, and other difficult matters; no agreement had been reached; probably none would ever be reached. But none is necessary, said Castellio; such disputes do not make men better; all that we need is to carry the spirit of Christ into our daily lives, to feed the poor, help the sick, and love even our enemies. It seemed to him ridiculous that all the new sects, as well as the old Church, should pretend to absolute truth and make their creeds obligatory on those over whom they had physical power; as a result a man would be orthodox in one city and become a heretic by entering another; he would have to change his religion, like his money, at each frontier. Can we imagine Christ ordering a man to be burned alive for advocating adult baptism? The Mosaic laws calling for the death of a heretic were superseded by the law of Christ, which is one of mercy, not of despotism and terror. If a man denies life after death, and rejects all law, he may (said Castellio) be justly silenced by the magistrates, but he should not be killed. Moreover (he thought), persecution of beliefs is futile; martyrdom for an idea spreads the idea far more rapidly than the martyr could have done had he been allowed to live. What a tragedy (he concluded) that those who had so lately freed themselves from the terrible Inquisition should so soon imitate its tyranny, should so soon force men back into Cimmerian darkness after so promising a dawn!77

Knowing Castellio’s sentiments, Calvin at once recognized his hand in the De haereticis. He delegated the task of answering it to his most brilliant disciple, Théodore de Besze, or Bèze, or Beza. Born in Vézelay of aristocratic lineage, Théodore studied law at Orléans and Bourges, practiced it successfully in Paris, wrote Latin poetry, charmed some women by his wit, more by his prosperity, lived a gay life, married, fell dangerously ill, experienced a sickbed conversion reverse to Loyola’s, adopted Protestantism, fled to Geneva, presented himself to Calvin, and was made professor of Greek at the University of Lausanne. It is remarkable that a Protestant refugee from a Huguenot-persecuting France should have undertaken to defend persecution. He did it with the skill of a lawyer and the devotion of a friend. In September 1554, he issued his De haereticis a civili magistratu puniendis libellus (A Little Book on the Duty of Civil Magistrates to Punish Heretics). He pointed out again that religious toleration was impossible to one who accepted the divine inspiration of the Scriptures. But if we reject the Bible as God’s Word, on what shall we build the religious faith that is so clearly indispensable—considering the natural wickedness of men—to moral restraint, social order, and civilization? Nothing would then be left but chaotic doubts disintegrating Christianity. To a sincere believer in the Bible there could be only one religion; all others must be false or incomplete. Yes, the New Testament preaches a law of love, but this does not excuse us from punishing thieves and murderers; how then does it warrant us in sparing heretics?

Castellio returned to the contest in a tract Contra libellum Calvini, but it lay unpublished for half a century. In another manuscript, De arte dubitandi, he anticipated Descartes by making the “art of doubting” the first step in the pursuit of truth. In Four Dialogues(1578) he defended free will and the possibility of universal salvation. In 1562, in Conseil à la France désolée, he appealed in vain to Catholics and Protestants to end the civil wars that were devastating France, and to allow every believer in Christ “to serve God according not to other men’s faith but to his own.”78 Hardly anyone heard a voice so out of tune with the time. Castellio died in poverty at the age of forty-eight (1563). Calvin pronounced his early death a just judgment of a just God.

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