On the Book of Jonah:
If this book had ended at the last verse of chapter 3, history would have portrayed Jonah as the greatest of the prophets. After all, preaching one message that motivated thousands of people to repent and turn to God was no mean accomplishment. But the Lord doesn’t look on the outward things; He looks at the heart (1 Sam. 16:7) and weighs the motives (1 Cor.4:5). That’s why chapter 4 was included in the book,for it reveals “the thoughts and intents” of Johah’s heart and exposes his sins.
If in chapter 1 Jonah is like the Prodigal Son, insisting on doing his own thing and going his own way(Luke 15:1132); then in chapter 4, he’s like the Prodigal’s elder brother–critical, selfish, sullen, angry,and unhappy with what was going on. It isn’t enough for God’s servants simply to do their Master’s will; they must do “the will of God from the heart” (Eph. 6:6). The heart of every problem is the problem in the heart,and that’s where Jonah’s problems were to be found.”But it displeased Jonah exceedingly, and he was very angry” (Jonah 4:1)…
For the second time in this account, Jonah prayed, but his second prayer was much different in content and intent. He prayed his best prayer in the worst place, the fish’s belly, and he prayed his worst prayer in the best place, at Nineveh where God was working. His first prayer came from a broken heart, but his second prayer came from an angry heart. In his first prayer, he asked God to save him, but in his second prayer, he asked God to take his life! Once again, Jonah would rather die than not have his own way.
This petulant prayer lets us in on the secret of why Jonah tried to run away in the first place. Being a good theologian, Jonah knew the attributes of God, that He was “a gracious and compassionate God, slow to anger and abounding in love, a God who relents from sending calamity” (Jonah 4 v. 2 niv).
Excerpt from The Wiersbe Bible Commentary: The Old Testament.