Furnace of Faith

It's easy to mix tin, copper, and lead with precious metals such as gold and silver. In fact, the valuable stuff often comes out of the ground mixed with these other metals. How do you remove these impurities, and how can you tell whether a gold coin or ingot really is worth its weight in gold?

The problem of testing or "assaying" precious metals has been around since ancient times. One very old solution relies on the different ways in which metals react with each other. Ingredients for this assay include a porous container called a cupel (KYU-pull), a chunk of lead, bellows for blowing air, a good hot fire and, of course, the stuff that's supposed to be gold. The method involves melting the lead and the gold in the cupel, while blowing air on the whole mixture. Oxygen in the air reacts with the lead, and the lead attracts every­ thing except the gold. At the end of the test, the lead and other impurities will have soaked into the cupel. When everything cools down, there should be a nice gold "button "sitting in the middle of the cupel. If the gold was not very pure, then the weight of the button will be a lot less than the weight of the original item. (By the way, the same test works for silver.)

The Bible tells us that God will assay us for our spiritual purity. Here is what He said to Jeremiah about the people of Jerusalem:

I have set you as an assayer and a fortress among My people, that you may know and test their way. They are all stubborn rebels, walking as slanderers. They are bronze and iron. They are all corrupters. The bellows blow fiercely. The lead is consumed by the fire. The smelter re­ fines in vain, for the wicked are not drawn off. People will call them rejected silver, because the Lord has rejected them (6:27-30).

In other words, the people of Jerusalem had no spiritual value. They presented themselves as the genuine article, but testing would show otherwise. God was going to look in His cupel, and He wasn't going to find a shiny button of pure faith in the people of Jerusalem.

One day, there will be a judgment in which God will assay the spiritual purity of all His people. In the meantime, we need to test our­ selves constantly so that we can avoid becoming impure (2 Corinthians 13:5). The life that we live on this Earth is a great furnace of faith. At the end of the test, our soul should be found pure in God's sight.