As God's Word, the Bible stands as final authority for faith and practice. What it says clashes with the world system and with man's depravity, so it will always be under attack by that system and by men. The more scripture has grown and will grow out of fashion with the culture, the more have denied and will deny its inerrancy. When I hear the term inerrancy, I think "without errors." I wish that was the definition. However, inerrancy itself, as most theologians understand it, does not mean "without errors," but "total truthfulness." Where the Bible speaks in matters of science and history, it is true, something like that. If you are going to believe the Bible to be totally truthful, you have some accounts therein that require faith to accept. They are statements beyond human explanation. If you believe in inerrancy, you accept all of those, as all the others, as totally truthful.
A few weeks ago, Albert Mohler, president of Southern Baptist Theological Seminary, reaffirmed and stood by the above definition of inerrancy, saying that there was no middle ground. You either believe it all or you don't believe it at all. But why do you believe it all? Some of it doesn't make sense. It clashes with what scientists say and what historians say. For instance, William Lane Craig (the youtube video is now gone, but the transcript is here) says that a vast, vast majority of New Testament scholars would regard Matthew's guard-at-the-tomb story as unhistorical. What authority does the Bible have when we can pick and choose what's true and what's not?
You exercise faith on many, many parts of the Bible. Some of it is beyond human comprehension. When you believe in inerrancy, you take it all as authoritative, even the hard parts, that have not had and may never have scientific or historical backing. Where it speaks, you say it is in fact science and it is as well history, even if you can't prove it with science and history. Maybe you can prove it with science and history and even most of it, but even if you could not, you would still believe it. It is true. It is authoritative. With inerrancy as a presupposition, I see every event, every statement, and every passage as scientific and historic. I think there is proof for it.
If the Bible says the truth about everything, then it also tells the truth about its own preservation. Inerrancy and preservation also dovetail with one another. If God didn't preserve the Bible, then that effects its inerrancy. If it isn't inerrant, then you've got errors anyway, and it can't be trusted. We should not relinquish the safety of inerrancy or perfect preservation. To believe either, we're trusting God. Both are historical positions. Inerrancy is attacked by historical criticism and perfect preservation is attacked by textual criticism. Both are the criticism of so-called science.
If Mohler were to be consistent, he would see the similarity of both inerrancy and perfection preservation. He would see the necessity of both. If the Bible is truthful, then it is perfectly preserved, because it says that it will be. If it isn't preserved, then the Bible isn't truthful, or it isn't inerrant. If God didn't preserve it perfectly, how are we to believe its inerrancy?
We have a safe place not just in inerrancy of scripture, but also in its perfect preservation.