The Bible condones slavery. And many slave holders invoked the Bible to justify slavery.
From Frederick Douglas' first autobiography:
Were I to be again reduced to the chains of slavery, next to that enslavement, I should regard being the slave of a religious master the greatest calamity that could befall me. For of all slaveholders with whom I have ever met, religious slaveholders are the worst. I have ever found them the meanest and basest, the most cruel and cowardly, of all others.
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