Got it in one. God's progressive revelation.
No wonder after two thousand years of following the first hippie western civilization is in such a mess.
That would be the western civilisation whose technology and social advancement soared above every other culture on the planet, and spread its ideals, idealogy and values to every corner of the globe? The one that embraced Christianity, right?
So . . . if the "old testament" is so meeeean, why are Jews so liberal?
Because they're @^%$&$ stupid and bite the hand that feeds them?
Which continued with the qur'an, Sikhism, mormonism, bahai, etc., etc., etc., etc. Looks like once you buy into "progressive revelation" there's no end to the matter.