The people of Nineveh repented after Jonah warned them
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Then Yahweh said to Jonah again, “Go to that huge city of Nineveh, and tell them the message that I gave you previously.”
So this time Jonah obeyed Yahweh, and he went to Nineveh. That city was very big. A person had to walk for three days to completely go through/see it. On the first day after Jonah arrived, he began walking through the city. He was proclaiming (OR, At the end of that day he started proclaiming) to the people, “Forty days from now, Nineveh will be destroyed [God will destroy Nineveh]!”
The people of Nineveh believed God's message. They all decided that everyone should begin ◄fasting/abstaining from food►. So everyone, including important people and unimportant people, did that. They also put on coarse cloth, to show that they were sorry for having sinned.
The king of Nineveh heard what the people were doing. So he took off his royal robes, and he also put on coarse cloth. He left his palace, and sat down where there were cold ashes, to show that he also was sorry for having sinned. Then he sent messengers to proclaim to the people in Nineveh: “My advisors and I have decreed that no one may eat or drink anything. Do not even allow your animals to eat or drink. Instead, every person must put on coarse cloth. Put coarse cloth on your animals, too. Then everyone must pray fervently to God. And everyone must stop doing evil actions/things, and stop acting violently toward others. Perhaps, if everyone does that, God may change his mind and be merciful to us, and stop being very angry with us, with the result that we will not die.”
10 When they all did that, God saw what they were doing, and he saw that they had stopped doing evil actions. So he pitied them, and he did not get rid of them as he had threatened to do.