Erwin Lutzer tells a story about a missionary who became a good friend of an Indian pearl diver. They had discussed salvation for many hours, but the Hindu could not believe that it could be a free gift. He believed that salvation could come by walking the nine hundred miles to Delhi on his knees. But the missionary said that salvation was so costly that Jesus had to buy it for us.
Before he left on his pilgrimage, the Indian gave the missionary the largest and most perfect pearl he had ever seen. The pearl diver explained that his own son had lost his life in getting this pearl from the bottom of the sea.
The missionary thanked him, but then insisted that he pay for it. The Hindu was offended, saying that there was no price that could be paid for a pearl that had cost him his son.