Proverbs 27:21-23

New International Version - UK

²¹ The crucible for silver and the furnace for gold,
    but people are tested by their praise.

²² Though you grind a fool in a mortar,
    grinding them like grain with a pestle,
    you will not remove their folly from them.

²³ Be sure you know the condition of your flocks,
    give careful attention to your herds;