A brick or stone structure used for various purposes, both domestic and commercial. Its design included a firebox, flue, heating chamber, and access opening. Furnaces were used for:
Smelting ore
Melting ore
Forging
Firing ceramics
Firing bricks
Making lime
The Bible mentions different types of furnaces. The potter's kiln, used for making lime and firing pottery, is referenced in Genesis 19:28; Exodus 9:8, 10; 19:18. These dome-shaped kilns, often made of limestone, had a chimney and a fuel hole at the bottom, producing thick, dark smoke.
While the Hebrews rarely used large smelting furnaces, except possibly during Solomon's reign, they were familiar with them from their use in Lebanon. Many Old Testament references to such furnaces are symbolic (Deuteronomy 4:20; 1 Kings 8:51; Proverbs 17:3; 27:21; Isaiah 48:10; Jeremiah 11:4; Ezekiel 22:18–22). A notable story involving a large smelting furnace is that of Shadrach, Meshach, and Abednego in Daniel 3.
The Bible often uses "furnace" metaphorically to represent God's discipline, punishment, or character refinement (Deuteronomy 4:20; 1 Kings 8:51; Isaiah 48:10; Jeremiah 6:27–30; Ezekiel 22:18–22). In the New Testament, "furnace" symbolizes hell (Matthew 13:42, 50; Revelation 9:2). The refining image also represents life's trials preparing one for the afterlife (James 1:12; 1 Peter 1:7).
In Revelation 1:15, John's vision describes the Son of Man with feet "like polished bronze refined in a furnace." This image of refined brass symbolizes Christ's power to defeat his enemies.