"Afflictions are God's threshing instruments to loosen us from the world, to part between us and our chaff, and to prepare us for use. God will proportion them to our strength; they shall be no heavier than there is need. When his end is answered, the trials and sufferings of his people shall cease; his wheat shall be gathered into the garner, but the chaff shall be burned with unquenchable fire." 

- Matthew Henry (commentary on Isaiah 28:23-29)