It is good for me to be afflicted. I am mended by my sickness, enriched by my poverty, and strengthened by my weakness, and with Saint Bernard desire, "Irasecaris mihi; Domine", O Lord, be angry with me. For if you chide me not, you consider me not; if I taste no bitterness, I have no physic; if you correct me not, I am not thy son. Thus was it with the great grandchild of David, Manasseh, when he was in affliction, "He besought the Lord his God": even that king's iron was more precious to him than his gold, his jail a more happy lodging than his palace, Babylon a better school than Jerusalem. What fools are we, then to frown upon our afflictions! These, how crabbed soever, are our best friends. They are not indeed for our pleasure, they are for our profit; their issue makes them worthy of a welcome. What do we care how bitter that potion be that brings Health. — Abraham Wright [most likely from A Practical Commentary on the Psalms,’ 1661]
It's worth adding another comment, this time from George Bowen [in his Daily Meditations]:
Even the profoundest affliction does not, perhaps, teach us everything; a mistake we sometimes make. But why should we compel God to use harsh measures with us? Why not sit at the feet of Jesus and learn quietly what we need to learn?