Pearl S. Buck said this quote

Wang Lung sat smoking, thinking of the silver as it had lain upon the table. It had come out of the earth, this silver, out of the earth that he ploughed and turned and spent himself upon. He took his life from the earth; drop by drop by his sweat he wrung food from it and from the food, silver. Each time before this that he had taken the silver out to give to anyone, it had been like taking a piece of his life and giving it to someone carelessly. But not for the first time, such giving was not pain. He saw, not the silver in the alien hand of a merchant in the town; he saw the silver transmuted into something worth even more than life itself - clothes upon the body of his son.