adjective

heretical

huh-RET-i-kul/həˈretɪkl/

Contrary to accepted religious doctrine or established beliefs.

Church leaders consider her interpretation of the sacred text heretical.

A scholar introduces a Sun-centered model into an ecclesiastical lesson built around an Earth-centered model; the clerics defend their established model and physically exclude the contrary one.

Etymology

The base meant “able to choose”; in religious use it described someone holding a doctrine at variance with established standards. The adjective applies that idea to beliefs or views themselves.

In context

Oculus Imperia13:52

deviation from the lex from the imperium is not only heretical in the most basic religious sense but an invitation to utter ruin

The Hexarchy Crisis: High Lords vs The Primarch (Warhammer 40K Lore)

More examples

The council condemns the preacher's teachings as heretical.
His heretical claim challenges the basic assumptions of modern economics.
In that department, questioning the founder's theories is practically heretical.

Forms

heretical

heresy noun — Belief contrary to accepted religious doctrine.

heretic noun — Person whose beliefs oppose accepted religious doctrine.

Similar words

unorthodox: Unorthodox often describes unconventional methods, not violations of doctrine.
heterodox: Heterodox emphasizes departure from prevailing opinion, especially in intellectual debate.