Adam and Eve were EXPLICITLY instructed not to eat from the tree. In contrast, murder or fratricide had not been explicitly outlawed! Humanity was never directly warned against taking another human life. Why then was Cain culpable for this crime?
“The lesson for us is that merely showing up in life just isn’t enough. Drifting along with no passion for living, or repeating the same good acts in a routine way is a kind of sin. Your acts are contaminated.”