Provide me with a Christian case for slavery, or racism then and I will show you how you could not support that from scripture and especially the forms of slavery that were practised in the nineteenth century African slave trade. But equally there is no case for homosexual practice in the Bible.
There are numerous examples in the Bible which promotes the idea of slavery, and provides rules and regulations on how to go about purchasing and treating slaves.
Hebrew slaves were treated essentially as indentured servants. However, there is a provision that if a master gives his slave a wife, and kids result of the marriage, the choice the person has is to either go free without his family, or to choose to not abandon his family and serve as a slave forever. (Exodus 21:2-6)
Non Hebrew slaves however were governed by Leviticus 25:45-46 in which it's plainly spelled out they are your properly forever, and may be passed on to your descendants as inheritance.
There's a number of other passages which spell out the price of slaves for a given age range and gender, and how you may treat them (for example, you're allowed to beat them as severely as you want, as long as they don't die within 1-2 days of the beating).
As for the New Testament, nowhere does it overturn the rules in favour of slavery, instead there's numerous passages which tell slaves they should serve their masters however the masters see fit.
For example:
Ephesians 6:5 - Servants, be obedient to them that are your masters according to the flesh, with fear and trembling, in singleness of your heart, as unto Christ.
1 Peter 2:18 - Servants, be subject to your masters with all fear; not only to the good and gentle, but also to the froward.
There's a few more passages that go along the same lines across multiple books if you would like to see them.
So yes, there's a strong Biblical justification for slavery for Jews, and Christians alike.