Isaiah 58:6

Let the oppressed go free - How can any nation pretend to fast or worship God at all, or dare to profess that they believe in the existence of such a Being, while they carry on the slave trade, and traffic in the souls, blood, and bodies, of men! O ye most flagitious of knaves, and worst of hypocrites, cast off at once the mask of religion; and deepen not your endless perdition by professing the faith of our Lord Jesus Christ, while ye continue in this traffic!