The ethical ideals of many who wrote the Bible scream out as primitive and barbaric. For many of the scribes responsible for the works of the Pentateuch, life was as uncomplicated as giving God exactly what he wants or starve and die of disease. Even promising that God would send wild animals to kill your children.
14If, however, you fail to obey Me and to carry out all these commandments, ...16then this is what I will do to you: I will bring upon you sudden terror, wasting disease, and fever that will destroy your sight and drain your life. You will sow your seed in vain,... I will proceed to punish you sevenfold for your sins. ... I will multiply your plagues seven times... 22I will send wild animals against you to rob you of your children, destroy your livestock, and reduce your numbers, until your roads lie desolate.
For later Christians like Marcion of Sinope, this was just unconscionable. Their solution might seem radical today. They insisted the God of the OT was not the true God but a demiurge pretender who had misled the Jews. It was impossible to harmonize the ideals of the Jesus they thought they knew with the God of the OT.