Jonah 4

Jonah was not happy when God did not destroy Nineveh. He was angry. God had responded to the repentance of Nineveh. He responded with mercy and grace.  He did not destroy them.  The message that Jonah preached, reached the hearts of the people and they had changed. God saw that change.  You would think Jonah would be happy, but he was not. Instead, he went up on the side of the mountain to sit and watch the destruction fall. He was excited about seeing Nineveh's demise.
He then began to complain to God.  He even said it would be better for him to die.  "4 Then the Lord said, “Is it right for you to be angry?”
God caused a plant to grow up and give him shade. Jonah was happy and loved the shade. But the next morning, God had sent a worm to eat the plant and it died. Jonah was in the heat and a terrible wind. Again, Jonah said it would be better to die.

9 Then God said to Jonah, “Is it right for you to be angry about the plant?”

And he said, “It is right for me to be angry, even to death!”
10 But the Lord said, “You have had pity on the plant for which you have not labored, nor made it grow, which came up in a night and perished in a night. 11 And should I not pity Nineveh, that great city, in which are more than one hundred and twenty thousand persons who cannot discern between their right hand and their left—and much livestock?”

We don't know of Jonah's response after that, but I do hope he realized that God was calling him to repent as well. Jonah needed salvation from a bitter, angry heart. He was not compassionate and loving to the people of Nineveh. God had just demonstrated His awesome love,, and Jonah had more pity on a plant than on the people in Nineveh.  God had let 20 thousand people and livestock live because they had repented.  Jonah wanted destruction. He had no pity. He did not recognize the salvation of the Lord. God was calling him to be saved, not from certain physical death, but from the spiritual wickedness, hatred in his heart. God calls his people to be pure in heart. The pure in heart shall see God. Hatred, strife and despair is not what God wants in the hearts of his people. Jonah had obeyed God and wanted his message to be fulfilled. Maybe his pride got in the way, or his self-righteousness about the Ninevites previous wickedness. Either way he did not want God to really forgive them.  He wanted destruction.  God showed him that mercy and compassion are really what God has for those that love him. God is a God of salvation.  I can only hope that Jonah recognized that message was for him too.  God wants to show compassion and mercy. Messages of destruction are to get people to change and repent.  Jonah hopefully came to the full understanding that God also loved him enough to forgive his sins.