Jonah 3:4-5

4When Jonah arrived in Nineveh, he walked for one day into the city. Then he shouted out to the people, ‘After 40 more days, God will destroy Nineveh.’

5The people who lived in Nineveh believed God's message. They told everyone that they must not eat any food for several days. Everyone had to wear sackcloth to show that they were sorry. The most important people and the ordinary people all did that.