Jonah became exceedingly angry at God for showing mercy to the Ninevites after they repented, displaying a misguided zeal that prioritized his own honor over God's compassion. His discontent stemmed from a perceived threat to his reputation as a prophet, as well as a jealousy for Israel's standing, reflecting his inability to accept God's broader plan for mercy and grace. Ultimately, Jonah's anger towards God's decision challenges the reader to reconsider their own prejudices and understanding of divine justice and mercy.