In-universe, just reading the Necronomicon drives you mad, and it contains knowledge that allows one to convene with extra-dimensional beings. Despite what some Christians might say about the latter point, and what some of their detractors might say about the former point, I have reasons to believe that the Bible does neither of these things, or does them extremely infrequently.
A better question would be "Does it contain secrets that make people straight up mad".
Have you seen a fundamentalist Christian before? Those people are bonkers.
Aaaaand called it.
People who say they understand the whims of otherworldly presences usually are bonkers, to be fair.
I mean the only real difference between "I kill all the heretics and make clothes from their skin because my god tells me to" and "I seriously believe that if I address my daydreamed wishes to my god that they'll come true" is the level of harm caused to society and other individuals by the outcome of those beliefs. You can believe whatever sort of crazy shit you want, paint it in the shades of religion or not, and as long as you're not infringing on others' rights you can go right on doing it. Naturally, most organized religion is extra-pushy and likes to annoy, convert, restrict, expel, or murder people who don't buy into what they're selling, depending on how strongly they dominate society.
But, like, in practice? I've known Christians of different stripes, a few Jews, a few Muslims, one Buddhist, and a range of pagans: all of them were equally bonkers when it came to the question of belief as far as I'm concerned, but for the most part they were fine people in all other respects, no more or less harmful than a guy I knew who genuinely believed that he could talk to ghosts. *Gallic shrug*