Biblical literalistic inerrancy is based on fear.
It’s not based on fear alone. There’s a positive side of the argument too, which essentially says that ‘if the Bible is inspired by God, then how can anything in it be wrong?’ That is actually an interesting idea, which I’m not addressing now.
But I’ve heard it consistently said that one of the main reasons to uphold inerrancy is that otherwise people will go off the deep end.
Here, I’ll argue that this fear is unjustified:
First, and obviously, people’s potential reaction to the idea that Scripture isn’t inerrant has nothing to do with the truth of the matter. (An interesting question is whether you would lie about it if you knew it would ruin their faith otherwise).
Second, I’ve seen plenty of good evangelicals make bad faith interpretations of Scripture to justify their behavior. Their belief in inerrancy did not reign them in. In fact, a lot of times Christians just do whatever they want without any pretense that the Bible, innerrant or not, justifies it.
Third, good-faith biblical interpretation is possible. The Spirit of truth and an open, honest, and humble heart lead people to a correct understanding of God, His word, His will, and His requirements. A hermeneutic does not save or sanctify. Who ever came to Christ because of a hermeneutic? Who ever grew in Christ or repented of any sin because they were finally convinced that the Bible was innerant and meant to be understood literally? Spiritual things happen by the power of the Holy Spirit through the various means, including the Bible, which He chooses.
In short, to the pure all things are pure. To the vile, all things are vile.