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

4:1 Hear this word, ye kine of Bashan, that are in the mountain of Samaria, which oppress the poor, which crush the needy, which say to their masters, Bring, and let us drink.