Alloy, of Metals

The mixing of base metals with precious ones serves as an image of corruption and impurity, and their removal as an image of divine purification.

Purging the Dross

Isaiah draws on the metallurgical practice of refining to depict Yahweh's judgment on Jerusalem. Isa 1:25 records the divine word: "I will turn my hand on you, and thoroughly purge away your dross, and will take away all your tin." Dross is the waste material that rises to the surface during smelting, and tin, when alloyed with silver, degrades its purity. The imagery frames Yahweh's action as a refiner's work — not destruction but purification, burning away what has corrupted the city.