Why did God eventually destroy Nineveh?

Nahum 1:14: “The Lord has given a command concerning you, Nineveh: ‘You will have no descendants to bear your name. I will destroy the images and idols that are in the temple of your gods. I will prepare your grave, for you are vile.’”

Nineveh was the capital city of Assyria, an ancient Mesopotamian civilisation located in present-day Iraq. Rich and powerful, the Assyrians were also known for their cruelty and idolatry.

God demonstrated his mercy to the Ninevites by sending Jonah to preach repentance to them (around 760 BCE). At that time, they responded to Jonah’s message, repented, and were saved from destruction. However, the Ninevites did not remain faithful to God, and various prophets, including Nahum, prophesied that they would one day face judgement. Nineveh eventually fell to the Babylonians in 612 BCE, a reminder that while God is merciful, he is also just.