Now the word of the Lord came to Jonah the son of Amittai, saying,“Arise, go to Nineveh, that great city, and cry out against it; for their wickedness has come up before Me.”But Jonah arose to flee to Tarshish from the presence of the Lord. He went down to Joppa, and found a ship going to Tarshish; so he paid the fare, and went down into it, to go with them to Tarshish from the presence of the Lord . - Jonah 1:1-3
http://www.biblegateway.com/passage/?search=Jonah1:1-3&version=NKJV
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Now the word of the Lord came to Jonah the second time, saying,“Arise, go to Nineveh, that great city, and preach to it the message that I tell you.”So Jonah arose and went to Nineveh, according to the word of the Lord. Now Nineveh was an exceedingly great city, a three-day journey in extent.And Jonah began to enter the city on the first day’s walk. Then he cried out and said, “Yet forty days, and Nineveh shall be overthrown!” - Jonah 3:1-4
http://www.biblegateway.com/passage/?search=Jonah3:1-4&version=NKJV
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So the people of Nineveh believed God, proclaimed a fast, and put on sackcloth, from the greatest to the least of them. . . . Then God saw their works, that they turned from their evil way; and God relented from the disaster that He had said He would bring upon them, and He did not do it. - Jonah 3:5,10
http://www.biblegateway.com/passage/?search=Jonah3:5,10&version=NKJV
Did God fully intend to destroy Nineveh? Or was he lying?