God forbade the Jews from kidnapping people and selling them into slavery (Exodus 21:16; Deuteronomy 24:7). The Apostle Paul also condemned the idea of capturing people with the intent of selling them as he described people who do such as ungodly and sinful (1 Timothy 1:9-11).
This picture of slavery is far removed from what took place in America or the African slave trade. It was not a matter of skin color. God uses all things in this world to bring about His glory.
Paul exhorted slaves to obey their masters, not because he approved the institution of slavery, but that it was a means of serving God. Christianity is not a political movement designated to defeat government, but addresses the sinful condition of the human heart.