The prophet Jonah didn't want Ninevah to repent and be spared the wrath of God. Jonah repented of His own disobedience while in the belly of the great fish, but even after being vomitted out onto a beach, he didn't want the Ninevites to be spared. He preached that the Ninevites would be destroyed in 40 days and they all repented, and destruction didn't come in 40 days, but it did eventually come. The Lord takes no pleasure in the death of those who are dying, but He knows the hearts of men, and men were born to trouble as the sparks fly upward (this phrase doesn't mean much if you haven't seen a wood fire.) If people really understood the holiness of God, and acted accordingly, destruction might never come, but salvation is through Christ alone.
Don't let your hearts be troubled for He has overcome the world.
Michael