If the Old Testament is divinely inspired by God, even a little bit, then I do not understand how it can sanction and promote so many egregiously wrong ideas, such as slavery:
As for your male and female slaves whom you may have: you may buy male and female slaves from the nations that are round about you. You may also buy from among the strangers who sojourn with you and their families that are with you, who have been born in your land; and they may be your property. You may bequeath them to your sons after you, to inherit as a possession forever; you may make slaves of them, but over your brethren the people of Israel you shall not rule, one over another, with harshness. – Leviticus 25.44
How can a "good" book say such a bad thing. How can a modern day Christian, many of whom purport to believe in the bible as the divinely inspired and (to many) inerrant work of God reconcile these words with our modern opinions on slavery. These (and others) are the words which emboldened and succored southern slave owners up to and during the American Civil War; these are the words which kept the "coloreds" in their place, separate and unequal.
The bible advocates many ideas and policies which we have (thankfully) long ignored, including stoning people to death for things such as working on the sabbath. If this work is divinely inspired why do the faithful not follow it more closely? If this work is divinely inspired by an omniscient God, how could it become so quickly outdated?
Christians (including the apostles) have been proclaiming the end of the world since the very early days of the church. Jesus' return, and the apocalypse He'd bring, was expected within a generation of His resurrection.
Children, it is the last hour; and just as you heard that antichrist is coming, even now many antichrists have appeared; from this we know that it is the last hour.
—1 John 2:18
But the end of the world hasn't yet come, despite the many dire predictions of mainstream and splinter groups over these last two thousand years. Most Christian groups have now wised up and stay well out of the prediction game, but some still swear it's going to happen any day now (next prediction for the end of the world is May 21, 2011).
The fact that the original church was wrong on this profoundly important point, and that many generally accepted as legitimate (as well as wacky) derivations of the original church have been wrong about this profoundly important point, makes me question how right they can be right about the less important issues.
The God of the Old Testament made his presence directly and unambiguously known in many people's lives. He spoke directly to various Biblical figures, sent angels to speak on His behalf to various others. He was a very hands-on God. And while He changed His interaction significantly in the New Testament (sending Himself in the form of His son to directly interact with people), he was still very hands-on. But for the last two thousand years His approach has been decidedly hands-off. Now admittedly it depends somewhat on which faith or at least sect you subscribe to. There are Christian sects who believe in the visitations of other prophets, visitations of angels, and miracles, but even among these groups I think it's fair to say that fellow parishioners would look askance at any one arriving Sunday morning claiming a previous night's visitation by an angel bearing a great revelation. Something changed in God's interaction with us, or perhaps in our interaction with God. In either case I find the change hard to reconcile, and belief discouraged as a result.
One trouble I have accepting Christianity as truth-based is the stark differences between the God of the Old Testament and the God of the New Testament. These differences seem peculiar to me. I would not have imagined an omniscient God would experience dramatic shifts in expressed personality over a span of a mere few thousand years. Our human personalities evolve greatly over our short lifespans because we acquire knowledge, we come to understand that knowledge, and we struggle with hormonal fluctuations that accompany the delicate process of growing and dying. God would have seemed immune to those issues, being both omniscient and omnipotent. And yet He seems to change.
This Old Testament God did a lot of punishing. For their disobedience Adam & Eve were cast out of Eden with all of us now suffering decay and death as a result. For man's growing wickedness all but Noah and his kin were killed in the flood. For their impenitent sin, everyone in Sodom and Gomorrah was killed except Lot and his two daughters. And for their enslavement of the Jews, all the first born males in Egypt were killed. And beyond all the punishment there is an awful lot of testing of men, including the horrible tale of Job and Abraham's near sacrifice of Isaac. And there are ever so many rules laid down in the Old Testament about the behavior we adherents are required to keep lest be kept out of heaven or deserve to be stoned to death. And of course there is the curious fact that Old Testament God is not described as a trinity.
The New Testament God is markedly different. God does not engage in widespread punishment, does not kill those who transgress upon Him or His son, Jesus. And God seems little interested in testing people's faith, except perhaps that of His son. And the New Testament seems to relay a doctrine primarily about love, tolerance, and the need to focus on the core Biblical principles (e.g., love thy neighbor) and less on the minutiae (e.g., don't eat shellfish). And somewhat surprisingly, God also revealed Himself to be a trinity, Father, Son, and Holy Spirit.
How can these two very different experiences of God be reconciled, without either admitting God Himself radically changed over a period of a few thousand years, or if God is the same then admitting that man's account of God must be wildly inaccurate? Both possibilities strongly discourage my belief.
If thousands of years ago the Old or New Testament had descended slowly from the heavens as a blinding light, settling on the ground and revealing itself to be universally intelligible words (readable by all men of every language) printed on indestructible paper as yet unexplained and unreproduced by scientists, then I would be strongly inclined to believe its contents are the unerring truths and wisdom of God. That's not what happened, however. Instead the Old Testament was thought to have been composed over some thousand years, from the 12th century BC to the 2nd century BC, passed down for much of that time by word of mouth. Not surprisingly subtly and significantly different versions of many of the stories/books exist, and various churches have different opinions about which books are valid and can be included. Thus it's very hard for me to imagine the Old Testament is the inerrant and factual testament of God. The New Testament has a similarly complicated history, not having been begun until well after Jesus' death, and then composed of varying, evolving books coming into and out of favor for some 1500 years or so, until stabilizing somewhat in the 16th century. Again, hard for me to see an evolving text subject to the apparent whims of various ages being the inerrant and factual testament of God. I cannot understand, knowing what biblical scholars do about the creation and evolution of the bible, how anyone can believe the bible is literally true.