Michael Servetus (/sərˈviːtəs/; Spanish: Miguel Serveto as real name, French: Michel Servet), also known as Miguel Servet, Miguel de Villanueva, Michel Servet, Revés, or Michel de Villeneuve (Villanueva de Sigena, Aragón, Spain, 29 September 1509 or 1511 – 27 October 1553), was a Spanish theologian, physician, cartographer, and Renaissance humanist. He was the first European to correctly describe the function of pulmonary circulation, as discussed in Christianismi Restitutio (1553). He was a polymath versed in many sciences: mathematics, astronomy and meteorology, geography, human anatomy, medicine and pharmacology, as well as jurisprudence, translation, poetry and the scholarly study of the Bible in its original languages. He is renowned in the history of several of these fields, particularly medicine. He participated in the Protestant Reformation, and later developed a heterodox view of the Trinity and Christology. After being condemned by Catholic authorities in France, he fled to Calvinist Geneva where he was burnt at the stake for heresy by order of the city's governing council.
Most scholars agree that Servetus was probably born in 1511 in Villanueva de Sigena in Aragon, Spain.
Servetus' family used a nickname, "Revés", according to an old tradition in rural Spain of using alternate names for families across generations.
Servetus was gifted in languages and he could have studied Latin and Greek under the instruction of Dominican friars. He also had a knowledge of Hebrew. At the age of fifteen Servetus entered the service of a Franciscan friar named Juan de Quintana. In 1526 he attended the University of Toulouse where he studied law. Servetus could have had access to forbidden religious books, some of them maybe Protestant, while he was studying in this city.
Quintana became Charles V's confessor in 1530, and Servetus joined him in the imperial retinue as his page or secretary. Servetus travelled through Italy and Germany, and attended Charles' coronation as Holy Roman Emperor in Bologna. He was outraged by the pomp and luxury displayed by the Pope and his retinue, and decided to follow the path of reformation. It is not known when Servetus left the imperial entourage, but in October 1530 he visited Johannes Oecolampadius in Basel, staying there for about ten months, and probably supporting himself as a proofreader for a local printer. By this time he was already spreading his theological beliefs. In May 1531 he met Martin Bucer and Wolfgang Fabricius Capito in Strasbourg.
Two months later, in July 1531, Servetus published De Trinitatis Erroribus (On the Errors of the Trinity). The next year he published the work Dialogorum de Trinitate (Dialogues on the Trinity) and the supplementary work De Iustitia Regni Christi (Christ's Reign) in the same volume. After the persecution of the Inquisition, Servetus assumed the name "Michel de Villeneuve" while he was staying in France. He studied at the Collège de Calvi in Paris in 1533. Servetus also published the first French edition of Ptolemy's Geography. He dedicated his first edition of Ptolemy and his edition of the Bible to his patron Hugues de la Porte. While in Lyon, Symphorien Champier, a medical humanist, had been his patron. Servetus wrote a pharmacological treatise in defence of Champier against Leonhart Fuchs In Leonardum Fucsium Apologia (Apology against Leonard Fuchs). Working also as a proofreader, he published several more books which dealt with medicine and pharmacology, such as his Syruporum universia ratio (Syrups
After an interval, Servetus returned to Paris to study medicine in 1536.
After his studies in medicine, Servetus started a medical practice.
In 1553 Michael Servetus published yet another religious work with further anti-trinitarian views.
To Calvin, who had written his summary of Christian doctrine Institutio Christianae Religionis (Institutes of the Christian Religion), Servetus' latest book was an attack on historical Nicene Christian doctrine and a misinterpretation of the biblical canon. Calvin sent a copy of his own book as his reply. Servetus promptly returned it, thoroughly annotated with critical observations. Calvin wrote to Servetus, "I neither hate you nor despise you; nor do I wish to persecute you; but I would be as hard as iron when I behold you insulting sound doctrine with so great audacity." In time their correspondence grew more heated until Calvin ended it. Servetus sent Calvin several more letters, to which Calvin took offense. Thus, Calvin's frustrations with Servetus seem to have been based mainly on Servetus's criticisms of Calvinist doctrine, but also on his tone, which Calvin considered inappropriate. Calvin revealed these frustrations with Servetus when writing to his friend William Farel on 13 February 1546:
On 16 February 1553, Michael Servetus while in Vienne, France, was denounced as a heretic by Guillaume de Trie, a rich merchant who had taken refuge in Geneva, and who was a good friend of Calvin, in a letter sent to a cousin, Antoine Arneys, who was living in Lyon. On behalf of the French inquisitor Matthieu Ory, Michael Servetus and Balthasard Arnollet, the printer of Christianismi Restitutio, were questioned, but they denied all charges and were released for lack of evidence. Ory asked Arneys to write back to De Trie, demanding proof. On 26 March 1553, the letters sent by Michel to Calvin and some manuscript pages of Christianismi Restitutio were forwarded to Lyon by De Trie. On 4 April 1553 Servetus was arrested by Roman Catholic authorities, and imprisoned in Vienne. He escaped from prison three days later. On 17 June, he was convicted of heresy, "thanks to the 17 letters sent by John Calvin, preacher in Geneva" and sentenced to be burned with his books. In his absence, he and his books were burned in effigy (blank paper for the books).
Meaning to flee to Italy, Servetus inexplicably stopped in Geneva, where Calvin and his Reformers had denounced him.
At his trial, Servetus was condemned on two counts, for spreading and preaching Nontrinitarianism, specifically, Modalistic Monarchianism, or Sabellianism, and anti-paedobaptism (anti-infant baptism).%2C%20p.%20141.]]f paedobaptism Servetus had said, "It is an invention of the devil, an infernal falsity for the destruction of all Christianity."procureur généralries—the most odd-sounding perhaps being, "whether he has married, and if he answers that he has not, he shall be asked why, in consideration of his age, he could refrain so long from marriage." To this oblique imputation about his sexuality, Servetus replied that rupture (inguinal hernia) had long since made him incapable of that particular sin. Another question was "whether he did not know that his doctrine was pernicious, considering that he favours Jews and Turks, by making excuses for them, and if he has not studied the Koran in order to disprove and controvert the doctrine and religion that the Christian churches hold, together with other profane books, from which people ought to abstain in matters of religion, according to the doctrine of St. Paul."
Calvin believed Servetus deserved death on account of what he termed as his "execrable blasphemies". Calvin expressed these sentiments in a letter to Farel, written about a week after Servetus’ arrest, in which he also mentioned an exchange with Servetus. Calvin wrote:
As Servetus was not a citizen of Geneva, and legally could at worst be banished, the government, in an attempt to find some plausible excuse to disregard this legal reality, had consulted other Swiss Reformed cantons (Zürich, Bern, Basel, Schaffhausen). They universally favoured his condemnation and suppression of his doctrine, but without saying how that should be accomplished.History%20of%20the%20Christian%20Church%2C%20]]Philip Melanchthon Libertines stake (while Calvin urged that he be beheaded instead). In fact, the council that condemned Servetus was presided over by Ami Perrin (a Libertine) who ultimately on 24 October sentenced Servetus to death by burning for denying the Trinity and infant baptism. Calvin and other ministers asked that he be beheaded instead of burnt, knowing that burning at the stake was the only legal recourse. This plea was refused and on 27 October, Servetus was burnt alive—atop a pyre of his own books—at the Plateau of Champel at the edge of Geneva. Historians record his last words as: "Jesus, Son of the Eternal God, have mercy on me."
Sebastian Castellio and countless others denounced this execution and became harsh critics of Calvin because of the whole affair.
Some other anti-trinitarian thinkers began to be more cautious in expressing their views: Martin Cellarius, Lelio Sozzini and others either ceased writing or wrote only in private. The fact that Servetus was dead meant that his writings could be distributed more widely, though others such as Giorgio Biandrata developed them in their own names.
The writings of Servetus influenced the beginnings of the Unitarian movement in Poland and Transylvania. Peter Gonesius's advocacy of Servetus' views led to the separation of the Polish brethren from the Calvinist Reformed Church in Poland, and laid the foundations for the Socinian movement which fostered the early Unitarians in England like John Biddle.
In his first two books (De trinitatis erroribus, and Dialogues on the Trinity plus the supplementary De Iustitia Regni Christi) Servetus rejected the classical conception of the Trinity, stating that it was not based on the Bible. He argued that it arose from teachings of Greek philosophers, and he advocated a return to the simplicity of the Gospels and the teachings of the early Church Fathers that he believed predated the development of Nicene trinitarianism. Servetus hoped that the dismissal of the trinitarian dogma would make Christianity more appealing to believers in Judaism and Islam, which had preserved the unity of God in their teachings. According to Servetus, trinitarians had turned Christianity into a form of "tritheism", or belief in three gods. Servetus affirmed that the divine Logos, the manifestation of God and not a separate divine Person, was incarnated in a human being, Jesus, when God's spirit came into the womb of the Virgin Mary. Only from the moment of conception was the Son actually generated. Therefore, although the Logos from which He was formed was eternal, the Son was not Himself eternal. For this reason, Servetus always rejected calling Christ the "eternal Son of God" but rather called him "the Son of the eternal God."
In describing Servetus' view of the Logos, Andrew Dibb explained: "In 'Genesis' God reveals himself as the creator.
In his "Treatise Concerning the Divine Trinity" Servetus taught that the Logos was the reflection of Christ, and "That reflection of Christ was 'the Word with God" that consisted of God Himself, shining brightly in heaven, "and it was God Himself" and that "the Word was the very essence of God or the manifestation of God's essence, and there was in God no other substance or hypostasis than His Word, in a bright cloud where God then seemed to subsist. And in that very spot the face and personality of Christ shone bright."
Unitarian scholar Earl Morse Wilbur states, "Servetus' Errors of the Trinity is hardly heretical in intent, rather is suffused with passionate earnestness, warm piety, an ardent reverence for Scripture, and a love for Christ so mystical and overpowering that [he] can hardly find words to express it... Servetus asserted that the Father, Son and Holy Spirit were dispositions of God, and not separate and distinct beings." Wilbur promotes the idea that Servetus was a modalist.
Servetus states his view clearly in the preamble to Restoration of Christianity (1553): "There is nothing greater, reader, than to recognize that God has been manifested as substance, and that His divine nature has been truly communicated. We shall clearly apprehend the manifestation of God through the Word and his communication through the Spirit, both of them substantially in Christ alone."
This theology, though original in some respects, has often been compared to Adoptionism, Arianism, and Sabellianism, all of which Trinitarians rejected in favour of the belief that God exists eternally in three distinct persons. Nevertheless, Servetus rejected these theologies in his books: Adoptionism, because it denied Jesus's divinity; Arianism, because it multiplied the hypostases and established a rank; and Sabellianism, because it seemingly confused the Father with the Son, though Servetus himself does appear to have denied or diminished the distinctions between the Persons of the Godhead, rejecting the Trinitarian understanding of One God in Three Persons.
Under severe pressure from Catholics and Protestants alike, Servetus clarified this explanation in his second book, Dialogues (1532), to show the Logos coterminous with Christ. He was nevertheless accused of heresy because of his insistence on denying the dogma of the Trinity and the distinctions between the three divine Persons in one God.
Servetus also had very unorthodox views on the end times.
Because of his rejection of the Trinity and eventual execution by burning for heresy, Unitarians often regard Servetus as the first (modern) Unitarian martyr —though he was a Unitarian in neither the 17th-century sense of the term nor the modern sense. Sharply critical though he was of the orthodox formulation of the trinity, Servetus is better described as a highly unorthodox trinitarian.
Aspects of his thinking—his critique of existing trinitarian theology, his devaluation of the doctrine of original sin, and his fresh examination of biblical proof-texts—did influence those who later inspired or founded unitarian churches in Poland and Transylvania.
Other non-trinitarian groups, such as Jehovah's Witnesses, and Oneness Pentecostalism, also claim Servetus held similar non-trinitarian views as theirs. Oneness Pentecostalism particularly identifies with Servetus' teaching on the divinity of Jesus Christ and his insistence on the oneness of God, rather than a Trinity of three distinct persons: "And because His Spirit was wholly God He is called God, just as from His flesh He is called man."
Widespread aversion to Servetus’s death has been taken as signaling the birth in Europe of the idea of religious tolerance, a principle now more important to modern Unitarian Universalists than antitrinitarianism. The Spanish scholar on Servetus' work, Ángel Alcalá, identified the radical search for truth and the right for freedom of conscience as Servetus' main legacies, rather than his theology. The Polish-American scholar, Marian Hillar, has studied the evolution of freedom of conscience, from Servetus and the Polish Socinians, to John Locke and to Thomas Jefferson and the American Declaration of Independence. According to Hillar: "Historically speaking, Servetus died so that freedom of conscience could become a civil right in modern society." 
Servetus was the first European to describe the function of pulmonary circulation, although his achievement was not widely recognized at the time, for a few reasons. One was that the description appeared in a theological treatise, Christianismi Restitutio, not in a book on medicine. However, the sections in which he refers to anatomy and medicines demonstrate an amazing understanding of the body and treatments. Most copies of the book were burned shortly after its publication in 1553 because of persecution of Servetus by religious authorities. Three copies survived, but these remained hidden for decades. In passage V, Servetus recounts his discovery that the blood of the pulmonary circulation flows from the heart to the lungs (rather than air in the lungs flowing to the heart as had been thought). His discovery was based on the colour of the blood, the size and location of the different ventricles, and the fact that the pulmonary vein was extremely large, which suggested that it performed intensive and transcendent exchange. However, Servetus does not only deal with cardiology. In the same passage, from page 169 to 178, he also refers to the brain, the cerebellum, the meninges, the nerves, the eye, the tympanum, the rete mirabile, etc., demonstrating a great knowledge of anatomy. In some other sections of this work he also talks of medical products.
Servetus also contributed enormously to medicine with other published works specifically related to the field, such as his Complete Explanation of Syrups and his study on syphilis in his Leonhart Fuchs, among others.
- Austrian author Stefan Zweig features Servetus in The Right to Heresy: Castellio against Calvin, 1936 (original title Castellio gegen Calvin oder Ein Gewissen gegen die Gewalt)
- Canadian dramatist Robert Lalonde wrote Vesalius and Servetus, a 2008 play on Servetus.
- Roland Herbert Bainton: Michael Servet. 1511–1553. Mohn, Gütersloh 1960
- Rosemarie Schuder: Serveto vor Pilatus. Rütten & Loening, Berlin 1982
- Antonio Orejudo: Feuertäufer. Knaus, München 2005, ISBN 3-8135-0266-X (Roman, Spanish original title: Reconstrucción.)
- Vincent Schmidt: Michel Servet. Du bûcher à la liberté de conscience, Les Éditions de Paris, Collection Protestante, Paris 2009 ISBN 978-2-84621-118-5
- Albert J. Welti: Servet in Genf. Genf, 1931
- Wilhelm Knappich: Geschichte der Astrologie. Veröffentlicht von Vittorio Klostermann, 1998, ISBN 3-465-02984-4, ISBN 978-3-465-02984-7
- Friedrich Trechsel: Michael Servet und seine Vorgänger. Nach Quellen und Urkunden geschichtlich Dargestellt. Universitätsbuchhandlung Karl Winter, Heidelberg 1839 (Reprint durch: Nabu Press, 2010, ISBN 978-1-142-32980-8)
- Hans-Jürgen Goertz: Religiöse Bewegungen in der Frühen Neuzeit Oldenbourg, München 1992, ISBN 3-486-55759-9
- Henri Tollin: Die Entdeckung des Blutkreislaufs durch Michael Servet, 1511-1553, Nabu Public Domain Reprints
- Henri Tollin: Charakterbild Michael Servet´s, Nabu Public Domain Reprints
- Henri Tollin: Das Lehrsystem Michael Servet´s Volume 1, Nabu Public Domain Reprints
- Henri Tollin: Das Lehrsystem Michael Servet´s Volume 2, Nabu Public Domain Reprints
- Henri Tollin: Michaelis Villanovani (Serveti) in quendam medicum apologetica disceptatio pro astrologia : Nach dem einzig vorhandenen echten Pariser Exemplare, mit einer Einleitung und Anmerkungen. Mecklenburg -1880
- Carlos Gilly: Miguel Servet in Basel; Alfonsus Lyncurius und Pseudo-Servet. In: Ders.: Spanien und der Basler Buchdruck bis 1600. Helbing & Lichtenhahhn, Basel und Frankfurt a.M. 1985, pp. 277–298; 298-326. (PDF; 64,1 MiB  )
- M. Hillar: "Poland's Contribution to the Reformation: Socinians/Polish Brethren and Their Ideas on the Religious Freedom," The Polish Review, Vol. XXXVIII, No.4, pp. 447–468, 1993.
- M. Hillar, "From the Polish Socinians to the American Constitution," in A Journal from the Radical Reformation.
- José Luis Corral: El médico hereje, Barcelona: Editorial Planeta, S.A., 2013 ISBN 978-84-08-11990-6. A novel (in Spanish) narrating the publication of Christianismi Restitutio, Servetus' trial by the Inquisition of Vienne, his escape to Geneva, and his disputes with John Calvin and subsequent burning at the stake by the Calvinists.
In Geneva, 350 years after the execution, remembering Servetus was still a controversial issue.
About the same time, a short street close by the stele was named after him.
The city council then rejected the request of the committee to erect the completed statue, on the grounds that there was already a monument to Servetus.
In 1942, the Vichy Government took down the statue, as it was a celebration of freedom of conscience, and melted it. In 1960, having found the original molds, Annemasse had it recast and returned the statue to its previous place.
Finally, on 3 October 2011, Geneva erected a copy of the statue which it had rejected over 100 years before.
Only the dates of the first editions are included.
- 1531 On the Errors of the Trinity. De Trinitatis Erroribus (Haguenau, Setzer). Without imprint mark or mark of printer, nor the city in which it was printed. Signed as Michael Servete alias Revés, from Aragon, Spanish. Written in Latin, it also includes words in Greek and in Hebrew in the body of the text whenever he wanted to stress the original meaning of a word from Scripture.
- 1532 Dialogues on the Trinity. Dialogorum de Trinitate (Haguenau, Setzer). Without imprint mark or mark of printer, nor the city where it was printed. Signed as Michael Serveto alias Revés, from Aragon, Spanish.
- 1535 Geography of Claudius Ptolemy. Claudii Ptolemaeii Alexandrinii Geographicae. Lyon, Trechsel. Signed as Michel de Villeneuve. Servetus dedicated this work to Hugues de la Porte. The second edition was dedicated to Pierre Palmier. Michel de Villeneuve states that the basis of his edition comes from the work of Bilibald Pirkheimer, who translated this work from Greek to Latin, but Michel also affirms that he also compared it to the primitive Greek texts. The 19th-century expert in Servetus, Henri Tollin (1833–1902), considered him to be "the father of comparative geography" due to the extension of his notes and commentaries.
- 1536 The Apology against Leonard Fuchs. In Leonardum Fucsium Apologia. Lyon, printed by Gilles Hugetan, with Parisian prologue. Signed as Michel de Villeneuve. The physician Leonhart Fuchs and a friend of Michael Servetus, Symphorien Champier, got involved in an argument via written works, on their different Lutheran and Catholic beliefs. Servetus defends his friend in the first parts of the work. In the second part he talks of a medical plant and its properties. In the last part he writes on different topics, such as the defense of a pupil attacked by a teacher, and the origin of syphilis.
- 1537 Complete Explanation of the Syrups. Syruporum universia ratio. Paris, edited by Simon de Colines. Signed as Michael de Villeneuve. This work consists of a prologue "The Use of Syrups", and 5 chapters: I "What the concoction is and why it is unique and not multiple", II "What the things that must be known are", III "That the concoction is always..", IV "Exposition of the aphorisms of Hippocrates" and V "On the composition of syrups". Michel de Villeneuve refers to experiences of using the treatments, and to pharmaceutical treatises and terms more deeply described in his later pharmacopeia Enquiridion or Dispensarium. Michel mentions two of his teachers, Sylvius and Andernach, but above all, Galen. This work had a strong impact in those times.
- 1538 Astrology and against a certain physician.
- 1542 Santes Pagnino.
- 1542 Biblia sacra ex postremis doctorum (octavo). Vienne in Dauphiné, edited by Delaporte and printed by Trechsel. Anonymous.
- 1545 Sacred Bible with commentaries. Biblia Sacra cum Glossis.  Lyon, printed by Trechsel and Vincent. Called "Ghost Bible" by scholars who denied its existence. There is an anonymous work from this year that was edited in accordance with the contract that Miguel de Villeneuve made with the Company of Booksellers in 1540. The work consists of 7 volumes (6 volumes and an index) illustrated by Hans Holbein. This research was carried out by the scholar Julien Baudrier in the sixties. Recently scholar González Echeverría has graphically proved the existence of this work, and demonstrating that contrary to what experts Barón and Hillard thought, this work is also anonymous.
- "Manuscript of Paris", (c1546).
- 1553 The Restoration of Christianity. Cristianismi Restitutio. Vienne, printed by Baltasar Arnoullet. Without imprint mark or mark of printer, nor the city in which it was printed. Signed as M.S.V. at the colophon though "Servetus" name is mentioned inside, in a fictional dialog. Servetus uses Biblical quotes in Greek and in Hebrew on its cover and in the body of the text whenever he wanted to stress the original meaning of a word from Scripture.
Spanish researcher Francisco Javier González Echeverría has done research that led him to identify Michael Servetus as the author or translator of 10 additional works between 1538 and 1553. These works were anonymous due to the first death penalty Michael got from the University of Paris in 1538, (finally reduced to a prohibition on "attacking" any Paris physician), its mention of authors who were forbidden in the Spanish Empire such as Erasmus and Robert Estienne, and the prohibition of any Biblical translation into any common language.
González Echeverría's conclusions have not been generally accepted by institutions studying Servetus, though they are supported by the International Society for the History of Medicine, the Spanish Society for the History of Medicine, and the Royal Academy of Medicine of Catalonia. The works that, according to this scholar, are also by Servetus are: 2 De Materia Medica with commentaries and marginalia (1543 and 1554, this last one printed by friends after Servetus' death), a pharmacopoeia of 1543, an edition of a Galenic corpus in 1548–1551, a manuscript ("Complutense's Manuscript") in an edition of De Materia Medica by Jean Ruel, as well as translations of two Biblical works with woodcuts by Hans Holbein the Younger: Picture stories of the Old Testament  and Portraits or printing boards from the story of the Old Testament. Finally, also translations from Latin to Spanish of four grammatical treatises, mostly for children: Disticha de moribus nomine Catonis, Children's book of notes on the elegance and variety of the Latin language, Andria. La Andriana, and A Little Work on the Use of the Eight Parts of Speech. González Echeverría is nowadays also the main defender of the hypothesis that Michael Servetus was born in the city of Tudela in the kingdom of Navarre, that both biological parents were actually Jewish conversos, although the father's identity and biographical details are unknown, and that his true name was "De Villanueva", while "Servetus" was a pseudonym that he used in Protestant lands, and for publishing his heretical theological works, showing no other data such as the city where they were printed, imprint mark nor mark of printer.
Some previous scholars had defended the birth of Michael in Tudela in the 19th and early 20th centuries, but never with the theory of "Servetus" being a pseudonym.
Regardless of whether he was really born in Villanueva of Aragon or in Tudela of Navarre, or somewhere else, the fact is that he was known as "Michael Servetus of Aragon" after his death by everybody, including Calvin and other enemies, his antitrinitarian supporters, and sympathetic authors such as Sebastian Castellio, and many others, both admirers and enemies of those theological works published by Servetus.