Diff, I think he's just saying that it helps to have a realistic understanding of just how much change the bible has gone through over the centuries (massive editing, things being lost or discarded, "creative" translations, etc), not to mention how much language has changed as well (people try to read the bible without considering the context of when it was written, so modern sensibilities and inferences seep in when it was never intended that way). I think it makes much more sense to view it as a guide rather than assuming a bible from the local Christian bookstore is the 100% accurate word of God.
Unless you're reading a first edition, of course. But I doubt it.
