There are many different reasons that bad things happen in the world. One important thing to remember is that disaster and suffering are not judgment from God unless someone prophesies that it will happen before it occurs. Nevertheless, there are differing reasons given in the Bible for suffering. This verse in Isaiah is one of them:
See, I have refined you, but not like silver; I have tested you in the furnace of misery.
Here the reason given for suffering is for purification. Just as silver is refined in a fire to remove the impurities, God used the suffering of the people of Judah to remove the impurities of their souls and leave a pure devotion to the Lord.
Whether there is a prophet to announces impending judgment or not, we can all use this approach to suffering in our own lives. If we allow the hardships in our lives to draw us closer to God, to depend upon him more, the cry out to the Holy One and be focused on him alone, then we will have been refined.
If, on the other hand, we allow the hardships and suffering of life to fill us with bitterness and rage towards God, then we will find ourselves further and further away from God in our lives.
It is a difficult choice to make–how to respond to suffering and hardship. I do not want to sound like I am making light of it. But if we can cry out in faith, even in the midst of everything going wrong, God will see us through and we will have an even stronger relationship with him because of it.