It is merely the very old fashion to attribute such rules to a deity. But they were simply the rules of our people so that we didn't steal or murder or go around making our parents look bad.
All these New Atheists who spit on the Jewish Bible are jackasses who neglect that these are actually the writings of people, not of deities.
But Christian Faith-Mongers have forgotten that what you believe doesn't matter one iota. What matters is how you behave towards each other.