Related Clues:

• Galileo, for one
• Inquisition target
• Freethinker, perhaps
• Unorthodox thinker
• Freethinker
• Nonbeliever
• Doctrine doubter
• Non-believer
• Inquisitor's quarry
• Unbeliever
• Excommunication candidate
• Inquisition victim
• Luther was one
• One seriously straying from the flock?
• One at risk of excommunication