Elsewhere I was challenged on the topic of how to defend the canonicity of the Bible - my response was this:

The Gospels & Epistles were orally preserved initially, and they are subsequently backed up by fragments that can date as far back as the 1st century AD. Probably at the churches of Jerusalem and other major centers of Christianity like Antioch, they already had the full Gospels and many epistles.

Because Christianity began spreading immediately from the time of Christ's death, with all of the Apostles dispersing throughout the region and far beyond, and St. Paul shortly thereafter doing his great trips through Asia minor, Greece, and Rome, we also run into the great defense against the heretics: heresies are localized distortions of Christian concepts with the exception of gnostics which were widespread since their context was often more from a theological big picture than some specific text disputing the Gospels.

So it was easy to recognize which texts were too localized; also the texts which have strange content that doesn't jive with the message at all are dismissable...
As far as the canonized Old Testament goes, there are rich disputes about how they should be structured, how they should be approached and interpreted, and I do not even think it is 100% essential to view these things as inerrant, but rather to believe them as God breathed and then recorded by man...

I read Israel Finklestein's Bile Unearthed, which was the big, scary text which proposed a radical new interpretation where the Old City of David couldn't have existed that early based on archaeological evidence..
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Finklestein does a great job outlining how much of the Old Testament narrative is demonstratably true, so much so that it is quite anomalous as far as ancient texts go which are often full of lies and embellishment. He suggested the only embellishment is really the timeline, and talked about how there is no evidence for Jerusalem having been a major city as far back as we have to put King David. Yet, in 2010, Eilat Mazar famously found what has been identified as a thousand year old, large wall that completely changes the concept that Jeruaslem was some unremarkable hill town and not an important place as the Bible says it is....