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 1

1:2 And he said, The LORD will roar from Zion, and utter his voice from Jerusalem; and the habitations of the shepherds shall mourn, and the top of Carmel shall wither.