The book of Amos can be divided into three parts:
Introduction and indictments against the nations, Judah and Israel (Amos 1:1 – 2:16)
After a brief introduction to the prophet (Amos 1:1–2), there are eight messages of judgment. The first six messages condemn foreign nations for injustice and oppression, primarily war crimes (Amos 1:3 – 2:3). The seventh message concerns judgment against Judah (Amos 2:4–5) and the final message focuses on Israel (Amos 2:6–16).
Judgment of Israel (Amos 3:1 – 6:14)
Three separate messages of judgment are all directed at the northern kingdom of Israel. They are accused of oppressing the poor (Amos 4:1; Amos 5:11) and worshipping improperly (Amos 4:4–5).
Visions of judgment and restoration (Amos 7:1 – 9:15)
Five visions of the judgment that awaits Israel are presented, followed by a promise of messianic restoration and blessing. The visions serve to reinforce the prophet's oracles against the nation and emphasize the certainty of destruction and exile.1
1 The words of Amos, who was among the shepherds of Tekoa, which he saw concerning Israel in the days of Uzziah king of Judah and in the days of Jeroboam the son of Joash, king of Israel, two years before the earthquake.