Calvinists often claim that if a Christian sins and doesn’t repent, that proves they were never truly “born again” to begin with. If that’s true, then John Calvin, the mind and soul behind Calvinism, isn’t saved according to Calvinism’s own decree.

The founder of Calvinism, John Calvin, played a central role in the arrest, trial, and eventual execution—effectively the murder—of the Spanish theologian and physician Michael Servetus in Geneva in 1553. Servetus was Calvin’s theological opponent, who rejected much of Calvin’s theology, including the doctrine of the Trinity.

John Calvin’s part wasn’t insignificant. Calvin—a lawyer—played a decisive role in Michael Servetus’s execution by providing evidence, pressing for conviction, and supporting the death sentence, though the final decision rested with Geneva’s civil authorities.

Calvin’s Role Summarized

• Prior hostility: Calvin and Servetus had corresponded in the 1540s, but Calvin came to see him as a dangerous heretic. He even wrote to Guillaume Farel in 1546 that if Servetus ever came to Geneva, “he would not leave alive”.¹
• Arrest and trial: When Servetus fled Catholic authorities and arrived in Geneva in 1553, Calvin’s allies quickly arrested him. The prosecution relied heavily on evidence Calvin had gathered from Servetus’s writings and their correspondence.²
• Court proceedings: Calvin personally appeared in court, argued against Servetus, and pressed the case that his anti-Trinitarian views were intolerable. He urged the magistrates to convict him of heresy and death.³
• Sentence and execution: Although Geneva’s magistrates formally sentenced Servetus to death by burning, Calvin did not oppose the execution. In fact, he asked for a “more humane” method (beheading instead of burning), but the council rejected this request.⁴
• Aftermath: Calvin further defended the decision publicly, writing polemics to justify Servetus’s death as necessary to protect Christian truth. This cemented his reputation as both a rigorous theologian and an intolerant enforcer of orthodoxy.⁵
• No repentance: In contrast with King David and the Apostle Paul, who repented of their wronging, Calvin never repented for his role in the execution of Servetus.

Calvin was not the sole authority who executed Servetus — Geneva’s magistrates issued the sentence — but he was the intellectual driver, prosecutor, and advocate for Servetus’s condemnation. Without Calvin’s involvement, Servetus likely would not have been arrested or executed in Geneva.

Calvinists are stuck in an impossible corner: they must justify Calvin’s behavior in order to remain loyal to Calvinistic theology. If they admit that Calvin’s actions were sinful, evil, or disqualifying, then Calvinism itself collapses under its own logic—because by their own standard, Calvin’s role in the execution of Servetus and his refusal to repent would prove he was never truly saved to begin with. And if Calvin wasn’t truly saved, then his theology wasn’t divine revelation at all, but merely the product of his own imagination—or worse. Either direction Calvinists take with this dilemma, Calvinism proves false.

Come deconstruct Calvinism with me:

1. History Skills, “Calvin and the Controversial Execution of Michael Servetus,” History Skills, accessed December 5, 2025. ↩︎
2. History Skills, “Calvin and the Controversial Execution of Michael Servetus,” History Skills, accessed December 5, 2025. ↩︎
3. “The Controversy of Michael Servetus’ Execution,” Calvin.edu – Meeter Center for Calvin Studies, accessed December 5, 2025. ↩︎
4. “The Controversy of Michael Servetus’ Execution,” Calvin.edu – Meeter Center for Calvin Studies, accessed December 5, 2025. ↩︎
5. John Piper, “The Servetus Affair,” Desiring God, accessed December 5, 2025. ↩︎