The first human to be 'born' rather than created, and the first murderer. This is according to the biblical history that we all believe to be the origin of our existence (Genesis).
It is hardly surprising if we have a penchant for killing one another. It is etched into our DNA.
We should thank God that we are not all psychopaths! Otherwise, we would point a gun and pull the trigger on anyone who shatters our peace of mind and infuriates us. That is the world from Cain's perspective.
Pulling the index finger is a precarious and delicate balance. Just a slight squeeze, and someone else is sent to meet their Maker.
How easy it is to take a life! To kill someone else!
With such a diverse array of people in the world, how could you ever know if they want to kill you?
If you are a hardline Islamic Iranian, you would want to kill anyone who is American. Death to America!
That is precisely the Cain within us.
We have no choice but to simply trust in human reason (sanity). Even though jealousy, self-doubt, and hatred are deeply ingrained in our blood.
The first human ever born, and a murderer. The blood runs deep.