My grandpa taught me firearm safety and had the same lesson: “Dont point it at anything you dont intend to kill.”

He also added a second point: “If you shoot it, you kill it, clean it, and eat it. No shooting animals for fun"

It was kind of a joke but still is a good lesson. Taking a life (of an animal) should never be a trivial act, even if it is sometimes necessary or worthwhile. He was vocally very anti-poaching so if I’d actually killed an animal without the right tags he would have never let me hear the end of it.

The idea that killing humans is wrong didn’t need to be stated explicitly.