Christianity and its persecution of freethinkers

This post by James McDonald originally appeared at Bad News About Christianity.

Burning of Jan Hus at the stake. Nearly six centuries later in 1999, Pope John Paul II expressed “deep regret for the cruel death inflicted” on Hus and added “deep sorrow” for Hus’s death and praised his “moral courage”. (Credit: Wikimedia Commons / Public Domain)

The term blasphemer was applied to anyone who disagreed with the current line taken by the Church hierarchy. Blasphemers were liable to a range of punishments which tended to stop them repeating their offence. For trivial cases they had their lips cut off, or were burned through the tongue, or had their tongue cut out, or torn out. For more serious cases they could also be sentenced to a quick death (execution) or a slow one (imprisonment on a diet of bread and water). St Thomas Aquinas regarded blasphemers as heretics, and heretics as blasphemers. For him heresy and blasphemy amounted to the same thing. Like a long line of influential theologians before him, stretching back to St Augustine, he advocated the death penalty for offenders, and this was the prevailing view of Protestant as well as Catholic scholars. The consensus was that there was no choice in the matter because God had been explicit:

And he that blasphemeth the name of the LORD, he shall surely be put to death, and the congregation shall certainly stone him: as well the stranger, as he that is born in the land, when he blasphemeth the name of the LORD, shall be put to death. (Leviticus 24:16).

The limited nature of the biblical definition of blasphemy was ignored completely, while the point was taken to be that to ignore blasphemy would be contrary to the word of God, and therefore a sin in itself. Many Christians advocated death for blasphemers by stoning, in accordance with Leviticus, but the law never adopted this method of execution, despite its being advocated by bishops and judges. Stoning was however frequently adopted by Crusaders and other Christian mobs, who tended to have unconditional trust in the bible’s requirements.

Since anyone who disagreed with the Church was necessarily guilty of blasphemy, and therefore liable to the death penalty, there were few people who would voluntarily come forward to declare themselves. There were however, over the centuries, a number of people who were insane, or mentally deficient, or in receipt of revelation from gods other than the Christian one, who made blasphemous statements and paid with their lives. Genuine blasphemers have played very little part in the development of Christian thought, but as we are about to see, alleged blasphemers have played a major role. All of the following have been regarded as blasphemers: apostates, humanists, pantheists, Unitarians, deists, and atheists.


An apostate is someone who decides to leave a religion to which he or she has belonged. Where people had been forcibly converted to Christianity, they often secretly continued to practise their original faith. To Christian eyes this constituted abandoning the Christian Church, and was thus constituted apostasy. Despite the risks, pockets of people throughout Christendom secretly managed to hang on to their original religions for many centuries, even though they must have known that they were likely to be killed if the Church authorities found out. Well into the Middle Ages remote European communities were still worshipping the gods of their Celtic and Teutonic ancestors in private. In public, everyone was obliged to subscribe the current version of Christian orthodoxy.

Christian authorities had to keep a close watch on other categories of potential defector, since Christians were frequently converted to other religions if they had the opportunity to find out about them. This type of apostasy was common on Christendom’s territorial borders where ideas were freely exchanged, but rare in the hinterland where ideas were firmly controlled. Christians who travelled beyond Europe were at risk from new ideas, and the Church has long been embarrassed by the fact that many Crusaders, fired by Christian zeal to kill God’s Moslem enemies, had ended their lives as Moslems, killing God’s Christian enemies.

Unlike Islam, Judaism did not seek converts from other religions, so there was less of a threat from Jewish beliefs. Even so, Judaism won the occasional convert, though such converts were not likely to enjoy a very full life with their new allegiance. In thirteenth century England a young deacon fell in love with a Jewess and converted to Judaism. For this he was degraded and excommunicated by a Church Council at Oxford in 1222, then burned alive. In 1267 Pope Clement IV ordered the Inquisition to proceed against Christians who converted to Judaism. Three years later two converts were killed at Weissenberg in Alsace (one of them a prior in a Mendicant Order). Presumably the danger continued, for the Papal bull authorising the Inquisition to investigate such cases was reissued in 1274, 1288 and 1290.

Since it was the practice in most mainstream Churches to baptise everyone into the faith as an infant, anyone could be found guilty of apostasy if they elected either to follow another religion, or to deny all religion. All apostasy was blasphemy, and the penalty for it was death, as required by God.


Until the Renaissance the Church was able, more or less, to enforce its monopoly of belief. But during the Renaissance, humanism flourished. Humanists emphasised the rights, abilities and achievements of mankind, but did not explicitly deny God. Indeed many key humanists were clerics. Humanism was the most liberal position tolerated at time – though all humanists still ran the risk of offending their more traditional colleagues, and ending up being burned alive at the stake. Humanists were generally highly educated, and they soon opened the doorways to an idea called pantheism.


According to pantheist ideas there is no personal God. What is called God is merely the Universe personified. In other words, the term God is an alternative word for Nature. Pantheism, had been known in ancient Greece and was (and still is) widespread in India. There were a number of variations on this theme, associating Nature with the deity. Here is Alexander Pope’s version:

All are but parts of one stupendous whole,
Whose body Nature is, and God the soul

Giordano Bruno was a sixteenth century pantheist. He identified God with the universe. He saw the divine everywhere, in every grain of sand, in all life, in the stars, in the infinite universe. For him, God was the soul of the universe. He thought that Aristotle had been wrong, and that existing Christian denominations were petty and narrow. For such heresies he was kept in prison for seven years, examined by a number of cardinals, condemned by a meeting presided over by the pope, and burned at the stake in Rome in AD 1600. The precise charges against him have disappeared from Church records.

A monk called Lucilio (or Julius) Vanini was also a sceptical minded humanist. He made the mistake of referring to nature as the “Queen of the Universe” and was tried by the Parliament at Toulouse. He was convicted of atheism and blasphemy in 1619. His tongue was pulled out with pincers and severed. Then he was garrotted and his body burned at the stake.

In the Netherlands, pantheist ideas were argued by the philosopher Spinoza (1632-77), who attracted violent reaction from both Christians and Jews. Although pantheists would continue to be executed as blasphemers, Spinoza made pantheism respectable, at least among educated humanists, who soon started asking themselves about doctrines such as the Incarnation and the Trinity.


During the Enlightenment, scholars became aware that the concept of the Trinity had developed over hundreds of years, that its only explicit mention in the bible was a fraudulent insertion, and that many early Christians had denied Jesus’ divinity. These scholars adopted, or returned to, the belief that there is a single God – or rather (in theological-speak) that God has one person rather than three persons. They are thus known as Unitarians (as opposed to mainstream Trinitarians). But to question either the Incarnation or the Trinity was regarded as blasphemous, and therefore deserving of death, a position held by Roman Catholics and Protestants alike. Michael Servetus, the famous anatomist, was burned in 1553 – perhaps the first Unitarian to die at the stake for his views. He had narrowly escaped the Inquisition, only to be arrested by Protestants in Geneva. Despite a safe-conduct, he was sent to the stake by Calvin.

The burning of Unitarians caused public unease in England, even in the sixteenth century. Further disquiet was expressed in 1612 when Unitarians were burned in London and Lichfield. But the established Church, the Church of England, was adamant. Unitarianism was blasphemous. In 1648 an Act was passed which specifically prescribed the death penalty for Unitarian and atheist beliefs, both of which were again classified as blasphemous. Few prosecutions were brought because Unitarians tended to be thoughtful and well educated – which meant that they were generally also rich, influential and intelligent enough to be discrete.

Religious doubt was by now common amongst the educated classes. Thomas Hobbes came as close to being an unbeliever as was then possible while keeping his life. He seems to have been largely responsible for an explosion of atheism among the upper classes in the mid-seventeenth century – and some who could not countenance outright atheism became pantheists. Unitarianism also flourished in the upper reaches of society. Men like Isaac Newton, who lived while the 1648 Act was still on the statute books, were obliged to conceal their Unitarian leanings. John Locke was fortunate to escape prosecution in 1695 for his Unitarian views. The poet Milton also kept his Unitarian views to himself during his lifetime. Joseph Priestly left England for North America where Unitarianism was the religion of the educated élite. Harvard University for example was largely Unitarian, prompting the sneer that its preaching was limited to the fatherhood of God, the brotherhood of man and the neighbourhood of Boston.

In England, a new Blasphemy Statute was passed in 1698 to protect Christianity from criticism. Under the Act it was an offence to deny the truth of Christianity, or any of the persons of Trinity. Penalties included loss of civil rights and imprisonment. Prosecutions continued. In 1763 John Wilkes, the parliamentary reformer, was charged with blasphemy, along with a number of other offences. In continental Europe the Church had a stronger grip than in Britain. In 1766 a French boy, the Chevalier de La Barre, was accused of singing irreligious songs, mocking a religious icon, damaging a crucifix, and failing to remove his hat while a religious procession passed in Abbeville. He was sentenced to ‘the torture ordinary and extraordinary’ to have his tongue cut out, to have his right hand cut off, and to be burned at the stake. Voltaire fought for his life and the case was referred to the French Parliament. The clergy insisted on the death penalty. The boy was tortured, then beheaded, and his body was burned along with a copy of Voltaire’s Philosophical Dictionary.


In the late 17th century Philosophers had developed a theory known as Deism, the most important form of which asserted that God did indeed exist, and had created the world, but he had simply set it going, then left it to its own devices. In particular, he no longer interfered with human affairs. It was as though he had wound up the universe like a clockwork toy, then gone away and left it running. This has been described as atheism with God. To conventional Churchmen it was atheism cleverly dressed up to avoid prosecution. Whether or not its proponents honestly believed it, and whether or not they were really atheists, we have no way of knowing. In any case if it was a ruse it did not work, for early deists were burned at the stake, or otherwise executed as blasphemers. In 1697 an eighteen year old medical student called Thomas Aikenhead was hanged in Edinburgh for holding deist views, and specifically for denying the Trinity. He was denied counsel, and despite recanting was condemned to death. There seems to have been no legal basis for this sentence, but he swung from the gibbet anyway, the last person in Britain to be executed by the state for his religious beliefs.

Rich, educated and powerful Deists flourished while others, less well connected, went in fear of execution. In the seventeen twenties Thomas Woolston was put under house arrest for the remainder of his life for voicing doubts about the resurrection and other bible stories. The Deist Thomas Paine, who was not so well connected, was obliged to flee the country after being outlawed in 1792 (following the publication of his Rights of Man). He was therefore not personally available for prosecution for blasphemous libel when The Age of Reason was published.

Although famous and influential people tended to escape prosecution, they were still persecuted in various ways. Adam Smith and David Hume for example suffered for their known scepticism. Hume was denied the chair of moral philosophy at Glasgow because of ‘the violent and solemn remonstrance of the clergy’. In France, Denis Diderot was imprisoned in 1749 for his Lettre sur les Aveugles, and lived under constant threat of persecution for his Encyclopédie.

Reprinted with permission from the author.

James McDonald is Fellow of the Royal Geographic Society in Britain, and holds a number of professional qualifications. He also holds an MA in mathematics from Oxford University, and an MSc in Operational Research from Sussex University. He lives in the South of France. His newest book is Beyond Belief: Two Thousand Years of Bad Faith in the Christian Church (Garnet Publishing, 2009). His website is

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