The story talks about all the other men on the ship throwing over cargo and asking one another to "call on their god" and ask him to reveal what is causing the storm.
When they found Jonah sleeping down below they asked him to call on his god.
Jonah knew exactly what needed to happen in order to appease God, he told the men "Throw me into the sea and the storm will cease!" The men were hesitant to do this and kept trying to row back to shore until they finally realized doing as Jonah asked may be their only option. So they did.
Immediately the storm stopped and the men turned to Jonah's God, the only true God, praising Him for sparing their lives.
In the past when I studied this passage I always focused on Jonah's story - how God sent a whale to get him where He had previously asked him to go. An amazing miracle!
But this time I paid attention to the whole story and realized that the first reason God perhaps had Jonah on the ship was to introduce these lost men to Him! Think of the story they had to tell their families and friends!! How the minute Jonah hit the water everything was still!
Our journey toward God is the greatest testimony we have to help us reach others for Christ! My prayer is for a very discerning spirit to recognize what God's calling me to do with my time. By living obediently and growing closer to Him each day, I hopefully won't ever have to be thrown into the sea to get my attention!