(IFF) there is variation in the interpretation of the holy scriptures (multiple Christian denominations) (THEN) the holy scriptures cannot be the true and plain, infallible, perfect, literal word of an all-wise and all-knowing god.
You don't know that.
I'm pretty sure I do know that, and you can too, by applying simple logic.
Nobody disputes the existence of a particular copy of the holy scriptures.
I can present the book and any two people, regardless of their preconceptions, can agree the book exists.
The words are also not in dispute. The words exist. We can agree on the words printed on the page.
I can even generously grant that this book and these words are "the one and only true and infallible word of god".
Great. That's great. We agree on that much. We agree up to that point.
The trick is, that even if we agree on everything up to this point, 100%, we still DON'T agree on the APPLICATION of those words.
How does this perfect book and these perfect words INFORM my daily life?
What PRACTICAL VALUE does this perfect book actually have?
That's the bright line.
That's the line between FACT and OPINION.
That's the line that clearly demarcates Catholic from Episcopal, that specific line is what distinguishes between Baptist and Methodist.
In one part it says, LOVE THINE ENEMY, and in another part it says, KILL ALL ENEMY CIVILIANS INCLUDING CHILDREN AND LIVESTOCK (except for the virgin females of course, give them to the Priests as servants for the rest of their lives).
What MEANING am I supposed to glean from this?
You are making a claim about something we cannot know. We are using this world's rules to apply to a place we don't even know exists.
This is not an intractable problem. These are real-world questions that demand "objective" (not-opinion-based) real-world answers.
I want what the Christians promise. OBJECTIVE MORALITY. Real-world, unambiguous, yes or no answers that are not context-sensitive.
When god says, "kill the child who curses their parent", THEN KILL THEM.
When god says, "one who marries a divorcee commiteth adultery" and "kill adulterers", THEN KILL THEM.
These are unambiguous statements. We know how the ancient Israelites interpreted these laws. This is not up-for-debate.