We already have several Meta posts that are there specifically for helping new visitors learn what is and isn't on-topic. The posts were made with this type of question in mind. The best course of action is to leave a friendly, helpful, polite comment explaining why a certain questions doesn't quite fit here, vote to close the post, and be patient with newcomers.
Typically I leave a comment like the following:
Welcome to the site. As a new visitor, I'd recommend checking out the
following two posts, which are meant to help newcomers "learn the
ropes": help page and
How we are different than other
As covered in that second post, this question is off-topic. We don't
focus on who is correct, we stick to what various denominations
Note that the above includes the fact that we don't focus on whether Christians, muslims, atheists, wiccans, or some other religion is "correct". We simply don't care to discuss what is "correct", "true", "real", "imaginary", etc. This site isn't about that any more than the sci-fi site is about whether warp drive or Time lords are real. We simply cover what it taught, just like that SE site covers what is written (or in a movie/tv show/series, etc.)
Other possible responses:
As phrased, this question is likely to attract a bunch of conflicting
personal opinions, which isn't really constructive on a StackExchange
site. See Real Questions have Answers.
In the example you linked to, this would be a valid argument. I can think of many reasons for people to believe the Bible, just as I can think of many reasons not to. It all boils down to a subjective determination on what evidence to accept, what evidence is convincing, and what you are willing to believe. It's an opinion question pure and simple.
If the question is salvageable through editing, I may ask if they mind if I edit it to bring it in line with site guidelines while still getting an answer to their original question, or I might point them to Tips for editing a question to make it suitable for re-opening
The question in your example wouldn't have been a good candidate for editing into site guidelines.
- I can think of ways to phrase it so that it's not an opinion question... "What are common Apologetic arguments for the validity of the Bible" but that would be too broad. (Many books have been written on the subject.)
- Each individual point in the question has a standard Apologetic answer (but that would be multiple questions, most of which have already been asked here so they'd be duplicates.) So I wouldn't bother trying to edit it or suggest that they do. I'd VTC and move on.
Finally, if the topic is interesting, or something I can't resist discussing, I might create a chat room and invite the user to discuss it there. I've seen several others do the same thing.
One last note, lest anyone claim we are out to silence atheists, that's not the case. Atheists and non-Christians are welcome here. They just need to follow the same rules we do. See Are questions from atheists welcome here?