For whatever reason, I didn't simply answer that it didn't change things and leave it at that; I let things develop into a larger discussion about puzzling concepts in the Bible and how they are interpreted. After all, that particular section is fairly tame compared to some other questionable quotes. So I mentioned Numbers 31:15-18, which speaks of giving virgin captives to soldiers, and various places in Joshua which discuss destroying whole towns right down to the women and children. And this led to Deuteronomy 25, which prescribes death for raping a betrothed woman (and death for both if it was consensual), yet raping an unbetrothed woman is a simple matter of 50 sheqels and marrying her (which, at first reading, does seem to imply that she is forced to marry her rapist. The Rabbinic interpretation of this is that it applies only to a very particular stage of female maturity, between 12 and 12½ years, and that marrying the rapist is at the girl's option. Even so, it seems pretty mild).
The point I was trying to make was that the Bible is just full of troubling quotes and lines, and this is nothing new: people have been writing commentary to interpret and explain them for centuries. You won't find anything that can't be explained or interpreted away, simply because someone else would have already found it, and if it really really couldn't be explained, the Bible would have already lost a lot more respect than it has. And I noted such things as the Bible's dietary prohibitions (in the case of certain fish, an “abomination” no less) and its apparent support of slavery, death penalty for gathering wood on Sabbath, etc. The Bible certainly does seem, at least, to espouse morals and ideals that are at odds with our modern views, and there are various ways of reconciling the two. There are various re-readings and re-interpretations of the Bible, or conversely actually rejecting one or the other viewpoint (e.g. rejecting the Bible altogether, or something like Orthodox Judaism rejecting the idea that eating shellfish is permitted).
This tends to lead people (like my correspondent) to appeal to some sort of “logic” or “common sense,” which really means “what I think is right.” My correspondent reckoned that Biblical dietary laws were really just health advice (and thus presumably are not as relevant today) and death penalty for Sabbath-breaking was a corruption introduced by the generations of scribes passing the text down. And he thought that death penalty for adultery but a 50-sheqel penalty for rape “makes no sense and lacks consistency,” and that such an explanation was “something bizarre psycho wacko.” Why? Because it doesn't fit his expectations, apparently. At this point people are no longer talking about what the Bible says, but rather what it should have said, i.e. essentially putting words in God's mouth because we know what he should have said better than the text does. Now, human-based morality is okay (I personally have my doubts that there is any other kind), but people should at least recognize that they are invoking it. Once you start picking and choosing what the Bible “should” have said or meant, any claim to Divine authority (if any) is severely weakened. Who are we to say which laws are no longer relevant and which are not? If dietary laws were just health advice, maybe the prohibition against homosexuality was just to increase fertility, in a society with a high infant mortality rate. Or conversely, maybe dietary laws have some deep cosmic meaning that is utterly beyond our understanding (God does say, after all, that his thoughts are infinitely beyond ours, see Isaiah 55:9).
Now, Christians perhaps have a slightly better answer to the above, with the concept of Supersessionism, which I readily confess to not knowing very well. Yes, there are some things more or less explicitly de-emphasized by Jesus (like the dietary laws, see Matthew 15:11), but what can we say about the rest? Sabbath is one of the Ten Commandments; has that one been rescinded? And generally very few of the reinterpretations credited to supersessionism actually have a basis in the text. Most are still more variants of “well, that law just doesn't make sense to me.”
So, rape might be a horrible crime to us, and thus not to be discounted with a mere fine, but it wasn't always seen so. I seem to recall in medieval Japanese literature, at least, rape was considered an expression of powerful, impulsive love: he would not even let her objections stand in the way of his love of her, and thus something actually borderline laudable. A woman's rights to her own body are a comparatively modern concept, at least in universal application. Slavery is universally reviled in modern Western culture, but it was a completely normal part of life in ancient times. The Bible discusses the laws of slavery (as something that is part of its society) in great detail, perhaps a little surprising for a people just rescued from slavery, but not so incredible. Certainly debtor's slavery was perfectly understood: when you have no money, you have to sell yourself.
OK, so this has been a lot of talking as if I'm trying to push Biblical divinity or something… quite the opposite. I don't make any such claims, and the point really is that I don't think anyone else should either. What I mean is, even if you believe that the Bible is divinely-inspired or whatever, unless you're willing to accept all of it at face-value (which itself would require a lot of interpretation), you really have no right to point self-righteously at the text to support your particular morals, since you have essentially rewritten it to your own meaning, and everyone else's rewriting is no less valid. This is something all too often forgotten by Bible-thumpers.