In July 2018, I attended a conference on the topic of the Old Testament in Africa. One speaker, Professor Kpobi, gave examples of how the Old Testament brings helpful corrections to some problems and excesses that are arising in Christianity in Africa. Among the examples he gave was the story of the healing of Naaman.
In African traditional culture, the person wanting healing would have to go through an ordeal. The purpose of the ordeal is to show that they are serious. So the healer might ask the person to bring the tongue of lion, or some other very difficult thing. The ordeal might also involve the person drinking something dangerous. But the story of Naaman shows that the prophet demands no ordeal at all. Dipping in the Jordan river is not an ordeal. In fact, it is so much the anti-ordeal that Naaman balks. African Christian healers who demand ordeals may not realize it, but they are borrowing from their African traditional religion and not from the Scriptures.
In South Africa, some people became very ill after a Christian healer told them that they must drink gasoline. The Old Testament stories of healing bring correction to such practices.