However, most religious moral codes change over time, Christianity’s included, even if the Scripture doesn’t. Slavery is a good example; what is accepted and regulated by Scripture would be utterly rejected as wholly immoral by most Chritians today. So to claim that religious morality is some how rooted to fixed, eternal moorings compared to that of non-believers is wishful thinking IMHO.
Yes, but we’re not actually talking about a specific moral code, we’re talking about the reason an external authority is necessary to justify any moral code. That’s true even of moral codes one doesn’t adhere to, from Buddhism to Zoroastrianism to the cannibals of Borneo. (Actually, I’m thinking of checking the latter out - I’m sure it’s not too bad a thing once you get past the shrunken head part).
No. Neither the Scriptures nor Christianity's moral codes change. God is the same yesterday, today, and forever.
Do some people who call themselves Christian decide that Biblical morals are too strict and confining, and should change with the times? Yes.
That's a different thing.
"Slavery is a good example; what is accepted and regulated by Scripture would be utterly rejected as wholly immoral by most Chritians today."
God no more "accepted" slavery than He accepts theft, murder, homosexuality, etc. He permitted slavery, knowing that it was part of a fallen, sinful world, while laying out rules to govern the practice. He did the same with divorce, which the Bible says He hates.
God gave slaves rights and privileges; the Israelites were under rules and restrictions that specified their proper treatment.
" So to claim that religious morality is some how rooted to fixed, eternal moorings compared to that of non-believers is wishful thinking IMHO."
It might be your opinion, but the facts say otherwise.