Jonah 2:9 But I will sacrifice to You With the voice of thanksgiving; I will pay what I have vowed. Salvation is of the LORD.” (Psalm 69:30)
What a change of attitude – at least for the time being. He goes from not doing what God says and then compounding it by running away — to being thankful and willing to do all that Jonah has said that he would do. And of course this includes going to Nineveh.