Heresy isn’t the same as doctrinal error.
Heresy is a willful disobedience of the truth–a willingness to proclaim publicly that the church’s official teaching is wrong.
Thus, heresy is a “moral offense, not an intellectual one.”
This is how Alec Ryrie, in Protestants: The Faith that Made the Modern World, explains the background belief (the nature of heresy as willful, moral disobedience) that motivated the Catholic church’s virulent opposition to Martin Luther’s teachings.
Luther, like any heretic that question the church’s orthodoxy, wasn’t just intellectually wrong, he was immoral–and he had to be treated accordingly. Luther was protected from physical harm by his regional German prince, which kept him from meeting the fate for his moral disobedience that so many other heretics met during the medieval period.He was spared a martyr’s death.
But Ryrie raises the question of who gets to claim the martyr title? Heretics can’t die as martyrs–not in the eyes of the church, anyway, because their deaths are consequence for their disobedience, not for their righteous stands for the truth.
You’ve got to die for the truth to be a martyr.
But who, then, decides what the truth is?
Ryrie explains that,
The problem, as St. Augustine had recognized in the fifth century, was that martyrs cannot in fact prove that their religion is correct by dying for it. People die for all kinds of beliefs, and they cannot all be right. Augustine concluded that the cause, not the death, makes a true martyr. If you die for the truth, you are a martyr, but if you die for an error, you are deluded or a servant of the devil. That may sound like self-serving relativism, but again, the role of the church is decisive. The truth is determined not by anyone’s private judgment but by the church’s collective voice, guided by the Holy Spirit. You might have honest scruples about doctrine, but how could your private doubts weigh against the certain authority of the church?
This was precisely the argument Martin Luther’s opponents threw at him. And Luther, utterly convinced of the truth he had perceived in Scripture, concluded, logically enough, that any authority that denounced that truth must be false. He was driven to deny that the church could authoritatively denounce heresy. That was itself almost the greatest heresy of all. Across Europe, the church’s traditional machinery ground slowly into action against the new Protestant enemy (87).