Because he is a son of a bitch.
...or....
To be more real...
The people who INVENTED the FICTIONAL CHARACTER known as "GOD" or "Jehovah" or "Yahweh" in the old testament were racist, sexist, short sighted jerk slavers who only cared about their immediate profit. They therefore needed something scary to back up their fallacies from authority that they could just take people and sell them as cattle, or treat women like shit, or rape and pillage.
Therefore...God.
...or....
To be more real...
The people who INVENTED the FICTIONAL CHARACTER known as "GOD" or "Jehovah" or "Yahweh" in the old testament were racist, sexist, short sighted jerk slavers who only cared about their immediate profit. They therefore needed something scary to back up their fallacies from authority that they could just take people and sell them as cattle, or treat women like shit, or rape and pillage.
Therefore...God.