The crucible is for refining silver and the furnace is for gold, likewise the Lord tests hearts.

As the crucible is for silver and the furnace is for gold, so a person is proved by the praise he receives.

Look, I have refined you, but not as silver; I have purified you in the furnace of misery.

After all, they are your people and your special possession whom you brought out of Egypt, from the middle of the iron-smelting furnace.

You, however, the Lord has selected and brought from Egypt, that iron-smelting furnace, to be his special people as you are today.

“Son of man, the house of Israel has become slag to me. All of them are like bronze, tin, iron, and lead in the furnace; they are the worthless slag of silver.

As silver is melted in a furnace, so you will be melted in it, and you will know that I, the Lord, have poured out my anger on you.’”

Those are the terms that I charged your ancestors to keep when I brought them out of Egypt, that place which was like an iron-smelting furnace. I said at that time, “Obey me and carry out the terms of the agreement exactly as I commanded you. If you do, you will be my people and I will be your God.

As silver, bronze, iron, lead, and tin are gathered in a furnace so that the fire can melt them, so I will gather you in my anger and in my rage. I will deposit you there and melt you.