Possible Clues:

• Doctrine at variance with orthodox position
• This is the place for Y to be unacceptable, it seems
• Dangerous pronouncements
• Divergence from orthodoxy
• Unorthodoxy - apostasy
• Opinion contrary to accepted beliefs of a religion
• Opinion contrary to orthodox belief
• Inquisition's bane
• Behold the ultimate in heterodoxy?
• Present sly student dropped, with refusal to conform