Jesus is white and whiteness is associated with godliness and divinity. But Satan is black and darkness is associated with evil and occultism. I have said before the Bible is one piece of propaganda used to enslave Africans psychologically, physically, socially and mentally. Christianity was used by its creators to promote white supremacy and black inferiority. We learn from the book of Genesis, Noah cursed his son, Ham' descendants who later became Africans. Europeans and Arabs used the doctrine of the "Curse of Ham" to justify chattel slavery and colonisation of the African continent.
Because it was believed that black people were cursed. Again, in the book of Exodus, the God of Moses defeated the gods of Africa in Egypt. At that time ancient Egypt was the most powerful empire in the world, but fall to the gods of Caucasians of the Middle East.