“Doesn’t the Bible teach that it is alright to own slaves and to even sell our children into slavery?”
An atheist friend of mine once posed this question to me, hoping, I believe, to demonstrate to me that Christians don’t really believe everything that is in the Bible because we don’t condone or observe some of the Old Testament practices that God allowed or even seemed to encourage among his people. The question is one worth looking at and comes from the book of Exodus: “When a man sells his daughter as a slave, she shall not go out as the male slaves do.” Why aren’t Christians owning slaves and selling their daughters into slavery? Let’s take a look at that question.
Firstly, there are different aspects of Gods will that the bible refers to. There is what is known as Gods “sovereign” will. Also known as Gods will of decree or his perfect will; this refers to the will of God as his sovereign control over all that comes to pass. “…he does according to his will among the host of heaven and among the inhabitants of the earth; and none can stay his hand or say to him, ‘What have you done?’” We will obey Gods sovereign will whether we want to or even know about it.
Another aspect of Gods will that the bible talks about is known as Gods “will of command” or his permissive will. This is the will of God that he commands us to do, but which we can choose – by virtue of our free wills – to disobey. We find this in the example of the Ten Commandments. This is a list of very specific “do’s and don’t’s” that are commanded by God, but which are disobeyed constantly.
God is immutable in his moral attributes, but he is a personal God who is involved in the day-to-day lives of his creation – a creation that is imperfect and sinful and possessing of a free will. There is no place in the bible that either endorses or encourages any follower of Jesus to own slaves. However, in the Old Covenant, God did allow for slavery. God, in his permissive will, allowed a number of practices under the Old Covenant which, nevertheless, were not part of his perfect will. Slavery is one example. Another example is divorce.
He answered, “Have you not read that he who created them from the beginning made them male and female, and said, ‘Therefore a man shall leave his father and his mother and hold fast to his wife, and the two shall become one flesh’? So they are no longer two but one flesh. What therefore God has joined together let not man separate.” They said to him, “Why then did Moses command one to give a certificate of divorce and to send her away?” He said to them, “Because of your hardness of heart Moses allowed you to divorce your wives, but from the beginning it was not so.
God made concessions under the Old Covenant for divorce, although he never wanted divorce to happen.
Secondly, Slavery was a fact of life in the ancient world. Victory in battle produced slaves – period. Even in New Testament times, slavery was a massive institution. It is estimated that in the first century BC, between 30 – 40 percent of the population of Italy were slaves. Slavery was vital to the economy and even the social fabric of ancient societies. Therefore, for his own reasons, God chose to regulate the cruelty of slavery rather than to ban it outright. Under the Law of Moses, he commanded that slaves be set free automatically during the year of Jubilee. He forbade cruel treatment of slaves. He commanded that they be allowed a certain level of access to the ceremonies of Judaism and so forth.
Although slavery still exists today in those parts of the world with predominately Muslim populations, it has been the work of Christian abolishinists throughout the west that has been responsible for the demise of slavery as an institution.
Thirdly, as for selling their daughters into slavery… The first rule in Biblical hermeneutics is to let scripture interpret scripture. That is, never try to interpret a verse by itself, but interpret it in its literary and cultural context. We follow this same rule with anything that we read. The Hebrew word “ebed” and the Greek word “doulos,” which are both translated as “slave” in the Bible, encompass a range of relationships whose usage must be determined by the context. If you do not interpret it in context, you can make a text say anything.
Slavery in the Old Testament was overwhelmingly voluntary, and was usually initiated by the slave or the slaves’ family as an economic and social benefit. This servitude could extend, at the utmost, only to six years. It was nearly the same as in our recent past, in cases of apprenticeship, where the parents bind the child for seven years, and receive from the master so much per week during that period. A man might, in accordance with existing custom, sell his daughter to another man with a view to her becoming an inferior wife, or concubine. In either case, the Bible clearly states, “If a countryman of yours becomes so poor with regard to you that he sells himself to you, you shall not subject him to a slave’s service.” 
Lastly, the Bible was never designed to serve as a manifesto on controversial political issues. It is rather primarily the story of how God, over time, has worked His sovereign will in this universe, and is still able to do so, through the hearts and minds and lives of those who trust Him.
Soli Deo Gloria
 Exodus 21:7
 Daniel 4:35
 Matthew 19:4-8
 See article “Slavery” at Encyclopedia Britannica http://www.britannica.com/blackhistory/article-24157
 Deuteronomy 15:12
 Leviticus 25
 See article “Christianity and slavery-Movement towards abolition” http://www.religioustolerance.org/chr_slav3.htm
 Leviticus 25:39