Smelting is another Scriptural image for purification. This is the process by which metal is extracted from ore. Most of us moderns have learned of it from diagrams or pictures of industrial processes performed in modern factories far removed from where we live. But to people of Biblical times, smelting was much more immediate and familiar. Large quantities of crushed ore were piled into ovens and heated with a charcoal fire while air was pumped in. The result was a lot of useless slag and a very small amount of more concentrated metal-bearing residue. Once you got enough residue, you did the whole process again to separate out more slag (or “dross"), and then typically again and again until you finally had something like workable metal (hence the reference in
Psalm 12:6 to “silver...refined seven times").
Every aspect of smelting was dirty, hot, backbreaking work. From making the charcoal to mining and crushing the ore to working the bellows to digging out the furnace, there was nothing glamorous about it. Smelting was a lot of work for very little return, but it was the only way to get metal, which was necessary for survival. It also provided an immediate object lesson in spiritual growth and maturity.
Granite is good, solid rock. You can hew it, form it, polish it, even engrave it, and it will hold up. Likewise iron is good metal, suitable for forging and hammering. But ore is neither good rock nor good metal. It is too crumbly and weak to serve as building material, too brittle to be hammered and formed, and even too soft to be used as an abrasive. If it isn't refined, it's useless.
This refining process illustrates two things. One is similar to the lesson of grain and chaff: what looks like a lot is in fact very little of value. A large pile of even high quality iron ore might yield a pound of iron; a large pile of a more precious metal such as copper or silver might only yield an ounce or so – and that only after lots of hard labor.
Another lesson is one that is directly used in Scripture several times: that the trials and struggles of this life are like the fire of the smelting furnace, used by God to separate out the precious spiritual maturity from the slag of the natural life. Thus when God in
Deuteronomy 4:20 referred to Egypt as “the iron furnace" out of which He had drawn His people, nobody missed the point. This was not only true personally, as individual Israelites could see how the struggles they'd endured had increased their dependence upon God, but also corporately. According to rabbinic legend, only about 20% of the children of Israel chose to make the Exodus – the remainder stayed behind in Egypt, and their identity and memory is lost to history.
God used this smelting image again and again throughout Scripture. “The wicked" were compared to slag in
Psalm 119:119, in
Isaiah 1:22-25 Isaiah states that the pure “silver" of obedience has become slag that needs to be purified by trial. God explains to Ezekiel in
Ezekiel 22:18 that the nation of Israel has become like slag. God uses the image of refining in
Daniel 11:35 to explain how "the wise" will be purified through difficulty, and in
Zechariah 13:9 God uses the same image to explain how He will deal with all His people. One of the final prophecies in the Old Testament,
Malachi 3:2-3 compares the Messiah to "a refiner's fire".
Which is an interesting thing to keep in mind during Advent. Excitement and anticipation builds as we prepare to celebrate the coming of the Messiah. A few of us even hope for the Second Coming. But then, the Jews were excited about the Messiah's coming, despite the stern warning of Malachi (read
Chapter 3 again) and the nearly brutal
words of John the Baptist in his day. The Jews (and we) hope for goodies and good times; what they (and we) are promised is smelting. Sure, the result is good, but it's very hard on the ore, and a lot of useless bulk gets thrown out along the way.
From this perspective, Advent looks less like a countdown to fun and more like a challenge to our courage and character. Do we have the
cojones to stand up and ask for "the treatment", knowing that smelting is not only painful to endure, but embarassingly revealing? How will we feel when the furnace cools and we learn that what we thought was a lot going in was mostly useless slag? ("That little hunk at the bottom is
it? The rest of this is just junk?") Yet that trial by fire is the only way we become what we're meant to be. Without it, we're nothing more than debris on a hillside.