adjective

impious

im-PYE-us/ɪmˈpaɪəs/

Showing disrespect for sacred things or moral duties.

The visitor's impious behavior places muddy boots on the church's prayer bench.

Disrespectful visitor lounges with boots resting on a small church prayer bench near a simple cross, careless laughing expression while reverent older visitor looks dismayed.

Etymology

Latin pius covered proper devotion and duty toward gods, family, and others. Its negation gives impious the sense of withholding the reverence owed to sacred things.

In context

TED2:26

I think there are ways -- and I'm being both very respectful and completely impious -- of stealing from religions.

Atheism 2.0 | Alain de Botton

More examples

She considers mocking another person's prayers an impious act.
They regard neglecting one's duty to aging parents as impious.
His impious remarks offend the worshipers gathered in the chapel.

Forms

impious

impiously adverb — Without respect for sacred things or duties.

impiety noun — Disrespect for sacred things or moral duties.

Similar words

irreverent: Can describe playful disrespect toward authority, not just sacred things.
sacrilegious: More specifically describes violating or misusing something considered sacred.