Antitrinitarians of the Reformation - From Michael Servetus to the Socinians

The Radical Reformer Michael Servetus

"Oh Jesus, Son of the Eternal God have pity on me!" - Michael Servetus

Early life of Servetus

Michael Servetus was born in Spain in 1511.1 This much about his birthplace is certain; he gave it as either Villeneuve or Tudela, Spain. Wherever he was born, he was a Spaniard who lived during a significant period in Spain’s history. The Moors were recently driven out of Spain, the Jews had experienced sufferings at the hand of the Inquisition and Spanish ships had lately come back from discovering a New World. Spain had just become a new world superpower and was giddy with its riches and power. Servetus was born during the height of Spanish power and influence. It is worth noting that Servetus experienced this newfound power of his homeland as a Renaissance man through his eclectic interests and with his knowledge of the Classical languages’ Latin, Hebrew and Greek.

Michael Servetus. Image courtesy of Wikipedia.

Michael Servetus. Image courtesy of Wikipedia.

Reading widely, he became familiar with the major authors of the ancient world, as well as those of the Jewish, Arab, and Christian world. He studied law at Toulouse, the most celebrated University in all Europe, although he never graduated.

Servetus as Physician

Michael Servetus was by trade a physician and surgeon and had a habit of cutting open bodies to search for any animating spirit that gave a human its life force. He enters the medical history books as the discoverer of the pulmonary circulation of the blood. But he enters the philosophical and theology history books as being the only known person receiving – and being subject to – a death sentence by Catholic church leaders and then Protestant leaders. He would become a touchstone of two movements that would outlive and ultimately replace the brutal theological wars of Europe – though not war itself sadly. The first was toleration towards those who do not share the same religious beliefs – freedom of through and freedom of religion. The second was the centrality of science and reason in observing the natural world – the end of nature as mythology. This last point is beyond the scope of this paper.

For these two reasons, Servetus was spared the fate of being a footnote in history. Not long after his death, debate began to rage amongst reformers how much toleration should be given to dissenters.

The steps were small and almost imperceptible, but the road from this event to freedom of thought and religion began to be built. Even the Catholic church had its discussions, opting instead to buckle down on dissent and focus on expanding its theological empire wherever it could, especially through the kings of France, Spain and Portugal.

The Forbidden Book

While at Toulouse2 he secretly read the Bible as reading it was forbidden to the students.3 Students are alike whatever age they live in. Those things which are forbidden become the most intriguing. Against authority, Servetus consumed himself in studying the Old and New Testament, its prophecies, its moral teachings, its message of salvation, its histories. It was during this clandestine reading of the forbidden text that he “discovered” the Bible made not one reference to the Trinity. He later wrote that in the Bible there was,

“not one word about the Trinity, nor about its Persons, nor about an Essence, nor about a unity of the Substance, nor about one Nature of the several beings.”4

Servetus had little difficulty describing who he was, nor did he hide his beliefs and views about Christianity as he experienced it in the mid sixteenth century. Right out of the gate, he never once denied that he was a “non-Trinitarian” to anyone who asked. In fact, he believed Christianity had lost its original understanding of the Trinity and as a self-appointed reformer to the world he sought to restore Christianity to its pure form.

Servetus’ motivation for his studies

Part of his rationale for trying to get a better grasp on the nature of the Godhead was that the Jews saw in the Trinity not Monotheism, as Christianity claimed, but Tritheism. The Arabs also rejected Christianity for similar reasons. Thus, Servetus wanted to find assurances within the Bible that neither the Jews nor Arabs had any cause for rejecting Christianity. He wrote in his synopsis for chapter one:

“The Trinity excites the derision of Mohammedans and Jews, though Mohammed holds Christ and the Apostles in the Highest honor.”5

Servetus and the Jews and Arabs in Spain

He believed the Jews and Arabs could be persuaded to join Christianity if they knew the Bible did not teach a Trinity. Upon his discovery of the absence of the orthodox Trinitarian formulations in the Bible he determined he was going to restore Christianity to its purer roots and bring the Jews and Arabs into the fold. Wilbur wrote,

“He was destined to become not a jurist, nor yet a priest, but a religious reformer, who was to make known to the world his great discovery, supplement Luther’s reform of abuses in the Church by simplifying its teachings and restoring the purity of its doctrines which the perverse subtlety of the Scholastics had rendered so confusing and sterile, and was thus, as he hoped, to open a way to a general conversion of Mohammedans and Jews to Christianity.”6

A step towards achieving this end occurred when, with the Franciscan Monk Quintana, he was brought to Bologna to witness the Coronation of the Emperor of Germany. At the court of Pope Clement VII he saw the abuses of the Church firsthand and this experience led him to “regard the official religion of the Church as hollow mockery”.7 He left the service of Quintana and at nineteen years of age headed north to the Reformed lands to achieve his mission. He was never to return to his native Spain. He went to the Swiss confederacy and the German city-states believing the Reformers would be more willing than Catholics to hear his new discoveries. He left hoping the Reformers would adopt his plan for the restoration of Christianity.8 It is hard not to admire his enthusiasm and to appreciate his naivety. Little did he imagine what lay ahead for him.

De Trinitatis Erroribus - On The Errors of the Trinity

Arriving in the Reformed lands, he came into contact with several leading Reformers such as Melanchthon, Butzer, Capito, Oeclolampadius, and perhaps Zwingli. Servetus even sought out Erasmus (it is uncertain they ever met), although at any rate Erasmus did not take him seriously. These reformers gave the twenty-year-old an audience but upon hearing his attacks on the Trinity they felt Servetus held dangerous teachings and they determined the Spaniard must be convinced of the errors of his theology.

Unable to be convinced, Servetus found himself opposed by virtually all these reformers. Undaunted, in 1531 he went to Basel, at that time a tolerant city for dissidents and then to Strasbourg9 to publish his views. It was in Strasbourg that he encountered some of the Anabaptists who would play a leading role in spreading Servetian thought. This included the leading Reformer Butzer.

Servetus’ most famous work, at least his most influential, was De Trinitatis Erroribus, libri septem written in 1531 in Latin which was published in Strasbourg, France.10 In English it is On the Errors of the Trinity. Perhaps against his better judgment Servetus proudly put his name on the cover as per Michaelem Serveto, alias Reves ab Aragonia Hispanum. Had he kept the work anonymous he might have escaped trouble, although the authorities probably would have suspected Servetus anyway. At any rate, The Erroribus was banned in Strasbourg as a heretical work and Servetus found himself persona non gratis.


De Trinitatis Erroribus, libri septem. Image courtesy of Wikipedia

Its reception amongst Reformers

This medium-length work circulated amongst the leading reformers. Luther called it “a most virulent book”11 and wrote that it opposed the Word of God and the Holy Scripture. Melanchthon said it was the source of dangerous opinions.12 Interestingly he wrote,

As for the Trinity you know I have always feared this would break out some day”, and “This does not please me that Servetus does not make Christ truly a natural Son of God”.13

He saw in the Erroribus a revived Paul of Samosata and Photinus. This was a recurring charge against Servetus. Even Quintana was outraged that his former acquaintance should turn out to be such a heretic. The Catholics as much as the Protestants saw in the Erroribus a dangerous heresy and determined to suppress it. The Inquisition was now ordered to arrest Servetus if he ever came within their jurisdiction.

The publication of the Erroribus was understandably not well received and the immediate effect on Servetus was his exile. The German and Swiss Reformers were concerned for the success of their efforts and anything that might jeopardize their work was carefully stamped out or disowned. The Emperor was Catholic and they did not want to give the Catholics any good cause to pressure the Emperor to restrict or stop the Reformation. Servetus and his thinking fell into that category. If Servetus was free to promulgate his views, the Catholics could claim that Protestantism was undermining the very foundations of Christianity and drifting into apostasy. Servetus and his book could not be tolerated and so Servetus was censured. Servetus eventually found himself without a safe haven in either Protestant or Catholic lands. So, at only twenty years of age he found himself a wanted man by both the Reformers and by the Catholics. In despair he believed his only escape was to migrate to the New World, perhaps South America.14 For an unknown reason he did not leave for the new world and instead assumed a name, Michel de Villeneuve and fled to Vienna.15

Why was the Erroribus so heretical?

What was the nature of this banned work? The Erroribus is now an extremely rare volume bound with several other treatises he wrote at the same time. It is a seven chaptered monologue with a loosely developed argument. Servetus began his analysis by looking at the man Jesus. He then proceeded to describe his understanding of the Godhead. Servetus described the Trinity as follows.

“Jesus, surnamed Christ, was not a hypostasis (or unique essence of the Godhead) but a human being…He, and not the Word, is also the miraculously born Son of God in fleshly form…not a hypostasis, but an actual Son. He is God, sharing God’s divinity in full…Christ, being one with God the Father, equal in power, came down from heaven and assumed flesh as a man. In short, all Scriptures speak of Christ as a man. (The Holy Spirit) is not a separate being, but an activity of God himself.”16

In Servetian Christology Jesus and God are the same being. Jesus is God who assumed flesh upon earth during the incarnation. Jesus is not a part of God nor an essence of God but is God himself in the form of human flesh. The Holy Spirit is God’s activity. This is not the semi-Gnostic formulation which characterized Servetus’ later work The Restitution of Christianity. The formulations of many other Reformation-era antitrinitarians also lacked a Gnostic edge to them. Consequently, it was the “early” Servetus antitrinitarianism as developed in the Erroribus that spread throughout Europe and not his later semi-gnostic formulation of the Restitution. Wilbur wrote,

“In so far as Servetus had influence upon the course of the religious thought in the reformation period or later, it was almost wholly due to the Errors and the Dialogues.”17

While Servetus was in exile the Erroribus had been circulating in Europe despite efforts to ban it. His work and the circumstances surrounding his controversy thrust him into prominence and people who had doubts about the Trinity saw him as a martyr or as a pioneer. Those who held doubts concerning the Trinity were sometimes labeled Servetian. That is not to imply that they had actually read the Erroribus even though they shared similar concerns and doubts about the Trinity.

Servetus was in exile from 1532 to 1553 and in that time antitrinitarianism developed in at least two areas: northern Italy in 1539 and Poland in 1546.

The Restitution of Christianity

Twenty years later Servetus had gone beyond reinterpreting the Godhead and developed a complete reinterpretation of all aspects of Christianity in a work he called The Restitution of Christianity. But this complete overhaul never found adherents. However, his earlier immature thinking on the Trinity did influence others and it is this earlier work which came to be Servetus’ theological legacy.

Servetus’ later work The Restitution had little influence primarily because it was so effectively banned.18 But The Restitution remains Servetus’ mature thinking.

The Restoration of Christianity

Christianismi Restitutio cover (French National Library). Image courtesy of Wikipedia

Translations: “The Restoration of Christianity ..[…]… for destroying the Antichrist and his followers” (Latin) ” .. And Michael appeared in Heaven..” (Hebrew) “.. and a fight was unleashed in Heaven..” (Greek).

What was the antitrinitarian concept in The Restitution?

Servetian antitrinitarianism in The Restitution of Christianity represented his mature thinking and the following is given for the sake of comparison. It is best termed Modalism. The Godhead described in this work can best be called modal. In this system the Godhead is monotheistic, but it is also Trinitarian in the sense that it is manifested historically whose one God expresses himself differently for different ages. God is manifested in five different ways for the five ages into which Servetus divided history. Jesus Christ is one of the five expressions of God. God is himself the hidden root, unseen and unnamed. Proceeding from him is the Logos as the first “circle” outside the hidden root. From the Logos comes the Word. From the Word comes the Son, Jesus Christ. Jesus is the expression of God in human form, a concept expressed in the Erroribus. Viewing the Servetian system as stated in terms of time, God has expressed himself through the means of progressive revelation over time and this structure is divided into five sections.

God has expressed himself in human history first as Elohim, then as El Shaddai, then as Jehovah, and finally as Jesus Christ. He is to express himself as a fifth and final mode at the initiation of the Millennium, a thousand-year period. When God expressed himself as Jesus Christ, he did so to establish a mediator between himself and humanity. But the terms Jesus and Christ only apply to the mode whereby God manifested himself as man. Thus, Jesus is, as Servetus says, a man created in Mary’s womb as a celestial being by the infusion of divine semen. This Jesus was celestial flesh,19 that is, flesh made from God, but who was before the incarnation the Word. After the resurrection the celestial flesh was put off and the Word reestablished itself.

This was Servetus’ mature conception of the Trinity. It is, according to Servetus, a Trinitarian formulation without the Scholasticism of the Athanasian networking. True, but it is also Pantheism10 whereby God enters the material world without polluting his own goodness and divinity and does so through a celestial, or heavenly Jesus. When Jesus ascended to heaven, he was not the man Jesus but the restored divine non-human Word. This demonstrates how much the thinking of Servetus changed during the intervening twenty years between the Erroribus and his execution in Geneva.

Servetus and Calvin

This unfortunate Spaniard received a death sentence by the Catholics in France and then by the renown Genevan Reformer John Calvin. The legal concept of double jeopardy hadn’t entered Western jurisprudence by then. In the broad brushstrokes of the Reformation, the charges that both the Catholics and Calvin laid against him are not that significant. The main charge against him was that he challenged two of the most fundamental doctrines of Christianity - the Trinity and Infant Baptism.

John Calvin from painting by Holbein

John Calvin from painting by Holbein. Image courtesy of Wikipedia

But other reformers in the mid sixteenth century also held those views. Servetus was not unique in his theology. The real significance lay in the fact that Servetus was a protestant Reformer who like Calvin was attempting a wholesale reformation and improvement of life in the Republic. Servetus saw himself in common cause with Calvin. That’s why he fled the reach of the Catholics in France to find refuge in Calvin’s Geneva. He expected rather naively that Calvin would embrace a fellow traveler. Little did he expect the fate what would await him.

Why did Calvin find Servetus so diabolical?

After listening to Servetus explain his positions, Calvin considered him so diabolical that in the midst of the rupture between Rome and the Reformers, Calvin found time to have common cause, at least in theory, with the Roman Inquisition which itself had condemned Calvin. The enemy of the Catholics shared an enemy with Calvin. Did that make these enemies friends? Not quite, but it sure made Calvin quite uncomfortable after Servetus’s execution.

It was the first time Calvin had supported the execution of anyone for heresy and the blowback against him was severe. He was charged with “copying” Rome’s practice of burning heretics. Only months before Servetus was condemned to death in Geneva by the city council by the recommendation of Calvin, the Catholic inquisition in Lyons had condemned the Spaniard in absentia on the same charges. Lacking a body to burn, the Inquisition decided just to burn him in effigy.

This was an extraordinary event. Probably those watching him burn alive couldn’t have foreseen the effect this spectacle would have on the course of western society. It had both a social impact and a theological impact. The idea of just letting others have freedom of thought and belief seemed so absurd to these people watching a human being roast to death in a fire. From a theological perspective, it brought into mainstream thinking a lingering debate within the Reformation about the Trinitarian formulation of the Godhead. Surprisingly, the Trinity was rarely discussed amongst both Church teachers and certainly not amongst the rank and file membership. In fact, questioning this became known as Trinitarianism.

For this ambitious mission he was condemned under the ancient Justinian law forbidding anyone to deny the Trinity (he didn’t) and pedobaptism (he couldn’t agree with baptizing children). With the Genevan reformer John Calvin as his chief accuser and after a lengthy trial Servetus was condemned to death and died by execution on October 27th, 1553. While sitting on the burning pile of wood he cried out

O Jesus, Son of the Eternal God, have pity on me!20

For the sake of the placement of an adjective (Eternal God rather than Eternal Son) he died. Yet, as it turned out, latter many died at the hands of executioner for that order of words, although it must be said almost as many were willing to recant. But of all the antitrinitarians of the reformation era who did not recant, it was Michael Servetus who because of the notoriety of his death and the impact of his first two treatises became historically the most significant rearranger of adjectives.

His experience was not unlike the guests in the home of Jan Trzycieski, a Polish dissident living at about the same time who began to have doubts about the Orthodox Trinity. But let’s not get ahead of ourselves. We will discuss the Polish antitrinitarians in due time. Servetus began secretly to have doubts about whether the Trinity as understood by the Catholic and even the Protestant churches was in fact Christian.

Servetus and religious tolerance

Servetus burning at the stake in the city of Geneva during the mid 1550s providing some serious entertainment for the locals and plenty of chatter around the tables in pubs and kitchens. Why did Calvin give the go ahead to “redeem his soul in fire”? Couldn’t he have just banished him out of the country? Of course, but that would have deprived the good citizens of Geneva with a spectacle. On the other hand, it showed the limits of Calvin’s tolerance. Zwingli, Calvin’s competitor for the hearts and minds of Protestant Europe based in Zurich, managed to also banish and/or execute dissenters. The precedent for public executions of heretics and dissenters in Protestant lands had already been made by Zwingli, so what was wrong with Calvin’s turn at being an executioner.

Turns out quite a bit.

Europe was splintering into massive powerful groupings and power was clearly on the side of the Catholic nations. Keeping a higher moral stand was all part of the propaganda against Papal rule. How could Calvin make any such claims if he was going about doing just what the Inquisition was busy at doing in France, Spain and elsewhere. When the Spaniard Servetus entered Geneva, he came there as a refugee believing that propaganda. Servetus wanted support from Calvin. Instead he found the limits of how far a person can go in coming up with novel ideas not sanctioned by existing authorities. And on this point Calvin and the Inquisition were on the same page.

How does this affect the reputation of Calvin?

And as it turned out, Servetus was not alone in questioning received notions of doctrine. He was just the most high-profile case. Far to the north and east lay the lands of the King of Poland and Lithuania ruled by Sigismund Augustus, a rather worldly-wise king who had a rather dim view of religion and doctrinal debates. He didn’t care much for his father’s staunch Catholicism. He was Catholic but didn’t care much whether his subjects were – as long as they were Catholic or Protestant or even Jewish or Muslim and made money for his Kingdom. He even extended this tolerance to any dissenting Protestant.

Servetus was executed in 1553. By this time Henry VIII had just ripped apart the Catholic Church in England and established himself as Defender of the Faith and head of the Anglican Church. The significance of this event for Europe cannot be underestimated. The mystic and aura of Rome had been tarnished. Henry showed Europe that the power and authority of Rome could be successfully challenged and overthrown.

This fact hadn’t gone unnoticed by the King of Poland. In northern Germany, the strength of Protestant forces grew and defeated many Catholic forces. It seemed the days were numbered for Catholic powers in northern Europe. This left Poland out on a bit of a limb. King Sigismund Augustus could see the writing on the wall and wanted an English-type state with himself as Defender of the Faith of Poland-Lithuania. Dissenters aided that project. And into that tolerant space entered the Polish Brethren.

Continue to next section


  1. Wilbur, E.M. A History of Unitarianism: Socinianism and its Antecedents. (Cambridge: Harvard University Press, 1947), Pg.53. The exact birth date is uncertain due to his conflicting evidence given at his trials in Lyons and Geneva. 

  2. Wilbur, Unitarianism, pg. 53. 

  3. Wilbur, Unitarianism, pg. 53. 

  4. Servetus, De Trinitatis Erroribus, pp. 32a,32b, as quoted in Wilbur, Unitarianism, Pg. 53. 

  5. Serveto, M. The Two Treatises of Servetus on the Trinity. trans. by E. M. Wilbur. Cambridge: Harvard University Press, 1932.) Pg. 5. 

  6. Wilbur, Unitarianism, Pp 53-4. 

  7. Wilbur, Unitarianism, Pp 55. 

  8. Wilbur, Unitarianism, Pp 55. 

  9. Wilbur, Unitarianism, Pp 59. 

  10. Servetus in the meantime wrote another work Dialogorum de Trinitate libre duo or Dialogues on the Trinity. It presented the same thesis as the earlier Errors but without the invective and was presented in a dialogue form as, Servetus hoped, a better vehicle to deliver his arguments. It received no better reception. Servetus developed his full religious system later publishing it in the work Christianismi Restitutio or The Restitution of Christianity in 1553 at Vienne; it was The Restitution became the cause for his arrest by the Inquisition and his death at Geneva.  2

  11. Bainton, Hunted Heretic, Pg. 67. 

  12. Bainton, Hunted Heretic, Pg. 67. 

  13. Bainton, Hunted Heretic, Pg. 67. 

  14. Bainton suggests Servetus sought to flee to South America perhaps by joining the Welser expedition to Venezuela. Bainton, Hunted Heretic, Pg. 74. Had he gone one wonders how History would have changed. But that is too speculative to merit further thought. What happened is “the best of all possible worlds” anyway. 

  15. The years in exile have been summarized in an appendix. 

  16. Serveto, M. The Two Treatises, Pg. 3. 

  17. Serveto, M. The Two Treatises, Pg. xviii. 

  18. Both The Errors and The Restitution are now very rare works although the former has been translated into English and widely available. Only three copies are known of the latter. Bainton indicates only five copies are extant of the Errors in his list of Works by Servetus. See Bainton, Hunted Heretic, Pg. 220. 

  19. With respect to the celestial flesh as understood by Caspar Schwenckfeld and Melchior Hofmann Bainton says that Servetus shared similar views with respect to the flesh of Christ as diefied flesh. Bainton writes, “Both (Schwenckfeld and Hofmann) were concerned as to the nature of the flesh of Christ. Schwenckfeld inquired as to the kind of flesh eaten in the Sacrament and answered that the Body of Christ was a glorified body. The view of Servetus of the deified flesh was very similar. Hofmann could not see how the sinlessness of Jesus could be conserved if his flesh were like our flesh and subject to infirmity and sin. Even the virgin birth was not a safeguard unless it were posited that Christ in the process of birth was not contaminated. He was not born of Mary but simply through Mary, said Hofmann. Without knowing it, he was reproducing the view of the ancient Gnostics. Here too Servetus’ theory of the deified body sounded similar. But Servetus also differed from both men. Schwenckfeld dated the glorification of the body of Christ from resurrection. Servetus said that the body fell like Manna from Heaven and - disagreeing with Hofmann - that Christ’s flesh was like our flesh because our flesh also is capable of deification.” Bainton, Hunted Heretic, Pg. 65-66. 

  20. Bainton, R. Hunted Heretic, Pg. 212.