Amos is the book of the herdsman from Tekoa, a small town in Judah. He receives a direct call from God to prophesy against the unrighteousness of both Judah and Israel. Amos is the first prophet to proclaim that God is the ruler of the whole world.

Amos 4

4:9 I have smitten you with blasting and mildew: when your gardens and your vineyards and your fig trees and your olive trees increased, the palmerworm devoured them: yet have ye not returned unto me, saith the LORD.