The Book of Nahum is a short book of prophecy where the Prophet Nahum narrates the downfall of the violent and oppressive people of Assyria. They had demolished northern Israel and its surrounding territories. It begins by having God appear and introduce Himself by saying that the unjust people will be punished. Nahum describes the downfall of nations because they went astray. It goes on to show the Babylonian assault on Assyria in stages until the capital city of Nineveh lay in ruin. After the fall, Nahum goes on to describe Assyria, whose rulers systemically built an empire by being unjust and cruel. Their downfall was their own doing, for they reaped what they sowed. The king of Assyria is killed with a verse that shows people rejoicing in his fate with no one coming to help. This book reinforces God's commandments to all nations to rule justly and be merciful toward the weakest people.