Charles Ellicott Commentary Jeremiah 6:29

"The bellows blow fiercely; the lead is consumed of the fire: in vain do they go on refining; for the wicked are not plucked away." — Jeremiah 6:29 (ASV)

The bellows are burned. — Better, burn, or glow. In the interpretation of the parable, the “bellows” correspond to the life of the prophet as filled with the breath or spirit of Jehovah. He is, as it were, consumed with that fiery blast, and yet his work is faulty.

The lead is consumed ... — Better, from their fire is lead only. A different punctuation yields, The bellows burn with fire; yet lead is the only outcome. The point lies in the fact that lead was used as a flux in smelting silver ore. The founder in the supposed case went on with his work until the lead was melted, but he found no silver after all.

Plucked away. — Better, separated or purified, as in keeping with the metaphor.