Nahun was an oracle who oracled destructiony shit about Nineveh (the Assyrian city).
The Lord’s Anger Against Nineveh- God is a badass who completely destroys every foe. He was mad at Judah, but now He is over it, so He is going to completely destroy Nineveh and its people in order to secure the release of His own people, the Israelites.
Nineveh to Fall- The title of this section pretty much sums it up.
Woe to Nineveh- Nineveh is full of liars and show-offy bastards. All of their nonsense started with one “harlot.” She is a wanton, lust-filled, sorceress, skank hoe who ruined it for everyone (there are a few different theories on this verse: the harlot could represent Assyria itself, spreading idolatry, or possibly just one really nasty lady ruining shit for everybody). So I’m (God) going to lift up her skirts and show everyone her nakedness. You think you’re so cool, Nineveh, but you’re no better than any of the other cities that I have destroyed. You think you have this great army, but all of your troops are women, so hah! (No really, it says that, “Look at your troops–they are all women! 3:13” Try and protect yourself, but I will destroy you. And everyone will be happy about it, because you’ve been dicks to seriously everyone.
Next up, Habakkuk!