To sin, we must make some kind of a decision, whether clear and firm, or vague and wishy-washy. For sin to be present, our freedom must somehow be involved. This means that we are always responsible, to some extent, for our sins. If we just make a mistake, we can’t call that a sin. If I take someone else’s luggage home from the airport because it looks like mine, that’s a mistake, not a sin. But if I grab someone’s briefcase while they are not looking and disappear with it into the crowd, that’s more than a mistake…