I don't believe the Bible for the same reasons I don't believe the Qur'an, Book of Mormon, Kojiki, Lotus Sutra, etc. Someone (cofty) already stated the point, but I will say it as well. Christians, like most religious believers, start with an idea that their belief is somehow sui generis so that any usual method of investigating its claims of truth is held to be inapplicable, unacceptable, or insufficient to Christianity. Look, for example, at perhaps the foremost Christian apologist William Lane Craig. He spends alot of time debating and writing books on how reason supports the truths of Christianity. However, in his book "Reasonable Faith," he lets the actual situation slip:
"May I suggest that, fundamentally, the way we know Christianity to be true is by the self-authenticating witness of God's Holy Spirit? Now what do I mean by that? I mean that the experience of the Holy Spirit is veridical and unmistakable (though not necessarily irresistible or indubitable) for him who has it; that such a person does not need supplementary arguments or evidence in order to know and to know with confidence that he is in fact experiencing the Spirit of God; that such experience does not function in this case as a premise in any argument from religious experience to God, but rather is the immediate experiencing of God himself" -William Lane Craig, "Reasonable Faith: Christian Truth and Apologetics," rev. ed. (Wheaton: Crossway Books, 1994), 31, 32.
Thus for Craig the truth of Christianity is not established by any of the arguments he makes, but rather on some religious experience which he claims is "self-authenticating." One should already see the problem with this criterion for establishing truth since not being indubitable (thus dubitable, i.e. subject to doubt) necessarily means it cannot be "veridical and unmistakeable." Craig's self-authenticating religious experience stands in the same tradition as Rudolf Otto who likewise sought to ground the truth claims of Christianity in a claimed superior religious experience that ultimately falls outside any of the usual methods of empirical inquiry. In this way, Christians simply use reasonable sounding arguments to supplement their experience so as to given their religion a superfical air of reasonableness. In point of fact, however, Christians do not take reason to be the arbitor in examining the claims of their religion. Thus we are led back to Augustine's fides quaerens intellectum (faith seeking understanding) where reason only serves as the tool for so called revealed truths which are "known" through faith. This is all quite clear from Craig who himself states that "Should a conflict arise between the witness of the Holy Spirit to the fundamental truth of the Christian faith and beliefs based on argument and evidence, then it is the former which must take precedence over the latter, not vice versa" (Craig 36).
One should see another problem with the use of this criterion to establish truth in the fact that religions outside of Christianity likewise have "veridical and unmistakeable" religious experiences which Christians ironically will not accept as establishing the truth of the claims those religions make. Instead, the Christian takes those experiences as due to the influence of demons or psychological self deception. Thus the religious experiences of others are dismissed outright in preference to their own experience which actually should be taken as no more credible than any other. Thus essentially, Christianity is true because it says it is true.
This claimed unique status for Christianity naturally flows into all aspects of Christian apologetics making them disingeuous and unconvincing. To take the example of "proof from prophecy," Christians maintain that the Jewish Scriptures prophecy in great detail about Jesus numerous times giving convicing proof that Jesus is in fact the Messiah of God. Thus Matthew 2:15 shows that Jesus' move back from Egypt "fulfilled" the statement found in Hosea 11:1 where God declares "out of Egypt I called my son." Of course turning to Hosea 11 itself one does not find any prophecy concerning the Messiah, but rather a poetic passage recounting Israel's early history of God's callings them out from Egypt and their subsequent turning aside from God to worship Baal. The Christian will quickly respond that the passage has "dual meaning" or "prefigures" Jesus and so is in fact to be taken as a prophecy about Jesus. Thus the argument is ultimately that the passage is a prophecy because Christianity says it is a prophecy and it was fulfilled in Jesus because Christianity says it was. Of course the reasonable person sees in this instance that Christians have simply stacked the deck by fabricating a prophecy out of the words of Hosea in order to create proof for a preconceived claim of Jesus' Messiahship so that the said "prophecy" is completely unconvincing. The Christian of course will be content in sitting in their "self-authenticated" truth which is supplemented by self-proclaimed proof all while looking down on or pitying those not accepting Christian claims as hard-hearted and obstinate or ignorant at the very best.
The irony is that when it comes to other religious traditions' deployment of similar proofs, Christians suddenly become critical and subject those claims to reasonable inquiry. Take for example the Mormon claim that the book of Mormon is prophecied in Ezekiel 37:16, 17. Christians here will point out the overall context which makes it clear that Ezekiel is speaking of a reunification of the kingdoms of Judah and Israel so that the Mormon claim that this is a "prophecy" concerning the Book of Mormon simply can't be sustained. Mormons, however, already accept that Ezekiel is talking about the reunification of Judah and Israel but that this reunification is only viable due to the restoration of both sets of Scriptures, the Bible and the Book of Mormon, so that they claim Ezekiel has a deeper significance here. Is the Mormon appeal to some deeper significance for Ezekiel's words taken seriously by Christians? Absolutely not. The Christian here makes the reasonable conclusion that clear contextual indications are what should guide the understanding of the text and that Mormons are simply appealing to some claimed deeper meaning so as to manufacture proof to support their beliefs. One should remember too that the truthfulness of the Book of Mormon is also said by Mormons to be guaranteed by a witness of the Holy Spirit, i.e. burning of the bosom, that they no doubt also take as "veridical and unmistakeable" but which Christians reject out of hand. Incidently, the Mormons for their part will simply decide that the witness of the Holy Spirit to the veracity of the Book of Mormon takes precedence over any of the counter arguments Christians might throw at them due to the same reliance on their religious experience that Craig makes clear for his own views. In this way, both sides end up talking at each other with each not listening to the other seriously for ironically the very same reason. Examples of such double standards as these show clearly how Christian apologetics are simply a charade which attempt to cloth the claims of Christianity, actually accepted on the basis of a religious experience, with an air of reason by arming itself with "proofs" that are expected to convince others which are actually formulated on bases that even the Christian apologists would not accept unless it serves to support their own position.
This brings us back to why I do not believe the Bible to be the inspired, inerrant word of God. Well the answer is quite simple. Unlike the Christian who finds a subjective religious experience supplemented by forms of argument which would not be taken seriously from others to attest to the truth of Christian claims, I simply apply the same standards to all religious claims and texts equally. Thus I examine the Bible using the same critical methodology I would to any other text of antiquity. That is not to disclude the possibly that the Bible could in theory be demonstrated to be the inspired, inerrant word of God, but that I have yet to see any evidence of this that could not be explained in a more reasonable way or could not be claimed for some other text. Christian claims of the Bible's uniqueness are only based on preconceived ideas that it is unique. In a sense, the Bible is indeed unique, but only in the sense that any text is unique. Of course Christians are arguing that the Bible is unque par excellence as is the Christian religion. It is certainly true that Christianity is unique in its claims, but this this does not translate into its being true. Buddhism is also unique in its claims which likewise does not make it true. Similarly the Bible is unique, but this does not translate into its being true any more than the uniqueness of the Lotus Sutra does. Arguments in support of the Bible's claimed uniquely unique status, such as prophecies, non-contradition, scientific knowledge, etc., all ultimately rest on assuming the Bible to be sui generis from the start and using a double standard of witholding it from the normal procedure of subjecting it to objective, rational inquiry. Thus, my not beliving in the Bible as the inspired, inerrant word of God is not because I am hard-headed, obstinate, or ignorant any more than the Christian is hard-headed, obstinate, or ignorant for dismissing Mormon claims for the Book of Mormon. Rather, I simply employ the same methodology that a Christian would to all texts equality and don't "play favorites" in the pursuit of truth.
-Mebaqqer