On to another point, all of mankind is sinful including the Jews. I think most Jews were probably not all that different than foreigners in surrounding countries, even including the ones which put on an outward appearance of righteousness, they were nevertheless as a den of wolves on the inside. So these Scriptures you have a problem with, the Levitical laws particularly, applied to both the regenerate and unregenerate Jew, the laws had a broader scope applying to all of Jewish society, they addressed the problems of that society during a particular time in history. I suspect the treatment of slaves in ancient Hebrew society as a whole surpassed the treatment of slaves outside of Hebrew society. I suspect that many of those who were already slaves were relieved when the Hebrews would visit their slave selling country and purchase them. Neither scenario sits well with our modern sensibilities, but consider the consequences of Hebrews going to other countries and setting them free in Israel. From what I understand, in ancient Israel the Lord desired His chosen people to be a separate people, and if the Hebrews allowed all slaves to be free and stay, they would have become overrun with slaves from surrounding countries and lost their identity as Israel. If on the other hand they cast them back out into where they came from, where the situation would turn from not great, to disastrous. Finally, as terrible as it is, slavery helped to support ancient economies and economic growth, without slavery many past societies would have entirely caved in long before they did. None of this is an attempt to justify, it is dealing with things as they were, with the problems that come with societies of sinners.