Killing for non violent behavior or for one’s beliefs occurs in almost all eras of history. The Old Testament is filled with episodes of killings based on idol worship, disobedience, dishonoring a parent, belonging to a particular ethnic group (such as the Amalekites), and unspecified offenses against God (see Genesis 38 and the story of Onan and his brothers). The New Testament tells the story of Jesus killed for his beliefs. The last two millennia are litanies of killings based on religion. The creed settled by the Catholic Church could not be easily breeched without punishment to heretics. Sometimes they lost their jobs. Sometimes they were imprisoned. At its worst, the heretics were put to death. The Reformation led to the death of Michael Servetus (not by Catholics but by Calvin who was outraged by Servetus’s heresies). It also led to the death of Giordano Bruno in Rome, also burned at the stake for refusing to reject his own beliefs and writings. Servetus and Bruno are unusual in their beliefs because they were priests of the Catholic Church who both rejected the Trinity. Servetus is a founder of Unitarianism with his book “On the Errors of the Trinity.” Bruno also rejected the virgin birth of Jesus and the transubstantiation of the blood and body of Christ during the ritual of the Eucharist.
What is also unusual is that both Servetus and Bruno were scientists. Servetus independently discovered the circulation of the blood (at least the role of the heart and lungs in “purifying” the air we breathe in and out). Servetus taught map-making, medicine, and astronomy as well as courses in theology. Bruno taught mathematics, mnemonic methods of memory, and astronomy as well as philosophy as he went through seven or eight universities in his teaching career. None of Servetus’s scientific work was at issue in his condemnation by both Protestant and Catholic agents seeking his arrest. It was luck that he was tried by Calvin’s court in Geneva rather than brought back to Italy for trial by the Church. Bruno’s science was tied to his religious beliefs and those scientific beliefs were only one of seven charges of heresy against him. Bruno accepted the Copernican model of a solar system in which the earth was the third planet orbiting the sun. He correctly identified the sun as a star. He then inferred that all stars had planets and that life must exist on most or all of them. He also believed the universe was infinite and thus life, the material world, and God are all names of one ultimate reality or God. That heresy the Church identified as pantheism.
Galileo also endorsed Copernicus’s model and offered evidence from his use of the telescope he made which revealed moons around Jupiter (he calculated their orbits and predicted their positions on any given day provided to him), craters and mountain ranges on the moon, Saturn’s rings (he called them “ears” because of the way they were tilted), the phases of Venus, and the sunspots on the sun which allowed him to calculate the sun’s rotation and proving the sun was not a perfect globe. Galileo was charged with disobedience because his published works ridiculed the prevailing Ptolemaic model of the earth as the center of the universe. Luther and Calvin were in full agreement with the Catholic Church that the heliocentric model should be condemned because it implied the biblical account of the universe was false. Galileo lucked out and avoided a death sentence. He chose to confess his error, denounce his publications, and spend the rest of his life in house arrest.
It took a long time for the crime of heresy to be seen as an error of belief and not as a capital crime. In many parts of the world heresy can still be used to justify a death sentence. Even where it may not be a government policy, individuals can convince themselves that heretics should be silenced by death rather than by the superior arguments they should try to muster in defense of their own beliefs.