The final chapter reveals Jonah's heart. When God spared Nineveh, it displeased Jonah exceedingly, and he was angry. In his prayer he finally explains why he ran to Tarshish: he knew that Yahweh is a gracious God and merciful, slow to anger, and abundant in loving kindness, and that he relents of doing harm. These words echo how God described himself to Moses. Jonah was so bitter that he asked God to take his life. Yahweh answered with a gentle question: is it right for you to be angry?
Jonah went out to the east side of the city, made a booth, and sat in its shade to see what would become of Nineveh. Yahweh God prepared a vine to shade his head and deliver him from his discomfort, and Jonah was exceedingly glad because of the vine. Then God prepared a worm at dawn, and the vine withered. God prepared a sultry east wind, and the sun beat on Jonah's head until he was faint and again wished to die.
God asked again whether it was right for Jonah to be angry about the vine, and Jonah insisted that he was right to be angry. God then drew the lesson. Jonah had been concerned for a vine he had not labored for, which came up in a night and perished in a night. Shouldn't God be concerned for Nineveh, that great city, with more than one hundred twenty thousand persons who can't discern between their right hand and their left, and also many animals? The book ends with God's question, inviting every reader to share God's compassion.