When Jonah disobeyed God's call to go to warn the people of Nineveh that they would be destroyed if they did not turn away from their wickedness, God showed Jonah that there was no way to hide from Him. Jonah had boarded a ship to run far away, but after the journey had begun a huge storm threatened to destroy the ship. Jonah was thrown overboard by the crew and swallowed by a giant fish where he remained for three days and three nights. After Jonah's fervent prayers to God, the big fish vomited the reluctant prophet back onto the land.
Then the word of the LORD came to Jonah a second time: "Go to the great city of Nineveh and proclaim to it the message I give you."
Jonah obeyed the word of the LORD and went to Nineveh. Now Nineveh was a very important city—a visit required three days. On the first day, Jonah started into the city. He proclaimed: "Forty more days and Nineveh will be overturned." The Ninevites believed God. They declared a fast, and all of them, from the greatest to the least, put on sackcloth.
Jonah 3:1-5 (New International Version)
God was not about to give up on Jonah. Once again the Lord's command came to Jonah to go to Nineveh with the message from God. We are not given many details about what the people of Nineveh were doing, but if we look at what is typical we can pretty well assume that they were involved with idol worship, immorality in many forms, and a general disregard for God's laws and almighty God Himself.
Nineveh was a city of over 120,000 people which would have been a very large city in that day. It was a center of commerce and was a major influence in the world at that time. The city set an example for society. The destruction of such a great city would have been devastating. However, a turning to God would have been a force in bringing many to recognize God's grace and mercy.
Despite his reluctance, Jonah successfully preached his message of warning to the people of Nineveh. His message was so persuasive that he brought the people to their knees in repentance. The Ninevites turned to God for the time being as a time of revival occurred in the city.
So often we fail in our own lives as Christians, but God does not want to lose us. God gives us many chances as we repeatedly fall into sin and come back on our knees in repentance. Fortunately, we have the record of Jonah and the other prophets to teach us the lessons that God's people had to learn and relearn. Even more importantly we have been given a redeemer in Jesus Christ. We have been given the Good News of the Gospel of Jesus Christ. And like Jonah we have been instructed to carry this Good News to the ends of the earth to all who will hear. We are sinners, but we are not doomed to eternal separation from God for He has given us a second chance through the sacrifice that Jesus made on the cross.
The men of Nineveh will stand up at the judgment with this generation and condemn it; for they repented at the preaching of Jonah, and now one greater than Jonah is here.
Matthew 12:41 (New International Version)