The Law of God in the Bible condones slavery. Oh don't try to deny it, it's absolutely true! It has rules for how to sell yourself into slavery (Exodus 21:1-6), how to sell your daughter into slavery (Exodus 21:7-11), and some crimes are even punished by selling the perpetrator into slavery (Exodus 22:1-3). It also has many different rules on how to treat your slaves (Exodus 21:20-21, cf. Colossians 4:1). And I believe that all of these laws ought to be adopted by our own nation. Well, those are fighting words in many parts of the country, I understand, but I believe that all nations are held accountable for how well they implement God's Law (compare Romans 13:1-7 with Revelation 13). Our nation has had a long and ugly history with slavery, though, and so to even suggest that such a thing be made legal makes the one doing the suggesting look like a racist and a bigot.
The truth of the matter, however, is that if this nation would have structured its laws to reflect the Law of God from the beginning, we never would have had the trouble with the institution of slavery like we did prior to the Civil War. The Law of God allows a man to sell himself to another man as a slave (apparently for the purpose of overcoming financial difficulty). The Law allows a father to sell his daughters (the feminists won't like that one, but then again, they're going to hate most of the Bible anyway), but it also protects those women from any mistreatment. The Law uses slavery as a punishment for crime - especially theft - and even allows wartime captives to be taken as slaves in some circumstances. But what we find absolutely forbidden in the Biblical Law is the taking of a man against his will (outside of a formal war) in order to make him a slave. In fact, the Bible states that if this is done, the one who 'stole' the man and any other person found in the possession of the 'stolen' man should be put to death (Exodus 21:16).
Imagine if that law were applied to the situation in the South prior to the Civil War. How many of those slaves that were being brought over here by the boatload do you think were 'stolen'? Many Southerners tried to defend the practice of slavery by saying that the Africans' own people had sold them to us, but we know that virtually none of those slaves came into the system according to the ways that the Bible prescribes. Practically all of them were stolen men (and women). If the Biblical Law were the basis of the system, though, those distinguished Southern gentlemen would be put to death as soon as it was determined that they were in possession of man who had been taken against his will. In fact, the whole African slave trade would never have been started in this country because of the fear of violating this command.
In addition, if our nation's laws were built around God's Law, we wouldn't have the kinds of problems that we have today with unemployment, an abused welfare system, and overcrowded prisons (actually, the Biblical Law has no place at all for incarceration). Someone who has fallen to the lowest rungs of society could easily sell themselves for a time to a wealthy family and be well taken care of while providing a valuable service. Those who have been reduced to theft in order to survive would be sold into the same system to make restitution for their crime, but also to be taken care of so that they would no longer have to steal.
The Old Testament's laws are not antiquated and naive. They have not been proven less civilized than modern American thinking in these areas. They reflect the perfectly just, good, and wise character of the benevolent God who gave them. Fallible and fallen man will never improve on them. This is as good of a blueprint for a Utopian society as you can get. Whenever someone complains that God's Law just doesn't work - like in the story of the Salem witch trials - the problem can always be traced back to those in the wrong not following the Law of God close enough. May those of us who are believers in Christ ever strive to show the holy character of God in the Law.