Isaiah

I, even I, am he that blotteth out thy transgressions for mine own sake, and will not remember thy sins.

And I will bring the third part through the fire, and will refine them as silver is refined, and will try them as gold is tried: they shall call on my name, and I will hear them: I will say, It is my people: and they shall say, The Lord is my God.

The fining pot is for silver, and the furnace for gold: but the Lord trieth the hearts.