Answer:
White southerners felt that it was important to show that the Bible sanctioned slavery because religion played a significant role in shaping their worldview and cultural values. Many white southerners were devout Christians who believed that the Bible was the word of God and provided guidance for all aspects of life, including the institution of slavery.
By claiming that the Bible sanctioned slavery, white southerners could justify the practice as morally acceptable and even ordained by God. They could also argue that abolitionists who opposed slavery were going against God's will and were therefore morally wrong.
Additionally, white southerners used biblical passages to argue that slavery was a natural and necessary part of society, and that slaves were inferior and needed to be controlled by their white masters. By using the Bible to support their beliefs, white southerners could avoid confronting the ethical and moral implications of slavery and maintain their social and economic power over enslaved people.
It's important to note, however, that not all Christians in the South believed that the Bible sanctioned slavery. Many abolitionists and other Christians argued that the Bible was being misinterpreted to justify a cruel and oppressive system, and that it was the duty of Christians to work towards the abolition of slavery.