I agree and the story of Jonah also shows us how our decision to do what God wants us to do or not do effects other people....like the people on the boat....and the people at Nineveh. (edit)
That is why there is so much pain and suffering in this world. People are like Jonah and their actions or lack of action is causing the boat to rock not only for themselves but for others as well.
As people start maturing in God's truth, there is less rocking. Of course I believe that only when Jesus returns will we have peace....until then, hold on tight to God's truth in faith. :)