I go into this a bit on this thread:
http://debatingchristianity.com/forum/v ... hp?t=27076
I would restate my thoughts but alas I'm short on time, here is what I said:
A sophisticated Christian (at least ones I talk to) would say this is a symptom of progressive revelation. That is, these things are just the Jewish people's laws, and like all other ancient cultures, they automatically attribute them to God. As you read the bible, which eventually accumulates into the New Testament, you see the Jewish people progressively developing a more advanced understanding of God. That is why, they claim, Jesus said he was coming at the "perfect time." The perfect time would be when the Jewish people were finally advanced enough, largely thanks to helenism, to have God actually come himself.
Jesus taught to not change anything about the OT, because if changed you would lose the important overarching story: That man continuously fails to properly discern God's will. The OT is therefore a story of the failure of man, and these absurd laws make sense in that they were indeed the distorted perception of man. The sophisticated Christian views the OT only in light of the NT, and Jesus.
The real problems come from the realization that this may be still true for the New Testament, that is that man's views distort the teachings of Jesus. We see this in that Jesus seems to teach conflicting things at times. Matthew, for example, portrays a very Jewish Jesus, seemingly belittling to gentiles, while other gospels portray him as almost the opposite.
These topics have to be dealt with in the grounds of the New Testament, the OT is an old covenant, probably distorted by the developing Jewish people. Christians aren't going to have their minds blown when you point out seemingly radical OT passages.
addition for this thread:
This in mind, it puts a new spin on the homosexuality debate. Of course we still have Paul's words in the NT, which is what many Christians would refer to as the source of their issue with homosexuality, but these are Paul's words, not Jesus'. Despite the apparent different perspectives the gospels seem to have on Jesus, an overview of what we can agree were generally his teachings seem to line up with what the OP is saying. Jesus was concerned with the heart behind the law, not the law itself. Perhaps certain laws were indeed good for a certain cultural context, but if one exalts the law above the innate morality Jesus claims we have, they have mistaken the purpose of the law. These were the kind of people Jesus fought against, and eventually died doing so. That point is not emphasized enough: Jesus died because he fought the religious.