In that film we were drawn into a world of profound evil swirling with angst and tension for no obvious reason. It is all the more frightening because at first all outward appearances suggest normalcy, wealth and promise with a vague threat looming. Slowly we see that sweet, doting grandmothers are actually coven leaders looking for a young woman to bear the devil's child and bring on the Age of Antichrist. The only thing resisting the diabolical plan is Mia Farrow's terror, and that's not much of a barrier to Beelzebub in heat. God is nowhere to be seen.
Religion is impotent or absent.
Goodness is not well defined. Evil is overwhelming and there is no stopping it. Finally Mia is resigned to the triumph of evil. It's hard to find. Here the opposition to overwhelming evil usually comes from panicky mundane people who finally get their dander up about the decapitations and slashings occurring all around them.