You might feel a little pain when you hurt someone, but you know, for them to do it, they've already prepared themselves mentally, and there are also certain things that force them to do so, such as basic biological goals, the power of the group influencing their behavior, etc. Their account within the group isn't their natural self, something they often mistakenly believe they are.
Of course, all humans are "evil" to some degree, but if everyone were evil to some extent at some point, the word "evil" would become meaningless. Replacing it with "heretic" would be more appropriate.
Human nature is inherently heartless towards outsiders; to gain power, you must first be evil, you must be extremely evil to seize power. The cult's structure over all groups of people is unavoidable.
This doesn't mean anything; of course the body will react, the degree of reaction depending on the mirror neurons and the life experiences of the perpetrator.