I answer that, with regard to heretics, two points must be observed: one, on their own side; the other, on the side of the Inquisition. On their own side there is the sin, whereby they deserve not only to be separated from the Imperium by excommunication, but also be severed from the world by death. For it is a much graver matter to corrupt the faith which quickens the soul, than to forge money which supports temporal life. Wherefore if forgers of money and other evildoers are forthwith condemned to death by the secular authority, much more reason is there for heretics, as soon as they are convicted of heresy, to be not only excommunicated but even put to death.
— Inquisitor Verelius, Warhammer 40,000, based from a quote by Thomas Aquinas
It is not our place to forgive the heretic, only to pray for his unworthy soul as his ashes ascend from the pyre.
— The Book of Castigations, Warhammer 40,000
"Incorrect. You can worship any gods you like. But Talos is a man, and only a heretic would think otherwise. And so you will die a heretic's death."
— Thalmor Justiciar, The Elder Scrolls V: Skyrim, after being told "I can worship whoever I want."