I have refined thee, but not with silver... — The meaning is obscure, and perhaps depends on some unknown process in ancient metallurgy. Commonly the refining of silver is taken as a parable of God’s dealings with His people (Isaiah 1:25; Ezekiel 22:18-22; Malachi 3:3). Here the thought seems to be that the discipline had been less fierce than that of the refiner’s fire. Silver was “purified seven times in the fire” (Psalms 12:6); but that would have brought about the destruction of Israel, and He sought to spare them.
I have chosen thee. — Better, I have tested thee.