Many diamonds, when they are found, have some stain or speck upon them, and they almost all have a rusty sort of coating, which must be taken off before their real beauty and brilliance can be seen. But this is a very hard thing to do. You know the diamond is one of the hardest things in the world. It is harder than iron, or steel, or stone. It is so hard that it will write on glass. It is so hard that nothing can be used to polish it but powder made out of diamonds.
When we become Christians we are like diamonds, as they are found in the mines. There are specks, or stains, on us, which must be removed by polishing. These specks and stains mean the bad habits we have formed, which must be broken up; or the bad tempers we have indulged, and which must be overcome. But there is one great difference here between diamonds and Christians, or between men’s jewels and God’s jewels. When a man is polishing a jewel, the jewel can’t help him. It has nothing to do. But if we are God’s jewels, when he is polishing us we must help him. There is something for us to do. And God won’t carry on the work of polishing us, or making us better, unless we try to help him.