The introduction provides the reader with certain information and with a particular perspective, both of which color the interpretation of the rest of the book. The superscription (v. 1) tells us that Amos was from Tekoa (probably Tekoa of Judah), that he was a shepherd, and that he prophesied during the reigns of Uzziah of Judah and his contemporary, Jeroboam of Israel, two years before the earthquake. The knowledge that Amos was from Judah is compatible with the book's claim that Yahweh dwells in Jerusalem (v. 2). Why should Yahweh choose a prophet from Israel if his dwelling place is in Judah? Moreover, the knowledge that Amos was from Judah informs the reader that the order by the priest of Bethel for Amos to “go back to the land of Judah” (7:12) meant a return to the prophet's homeland. The statement that Amos was “among the shepherds” indicates that Amos was not a lifelong prophet, thus giving support to Amos's claim in 7:15 that he had been taken from his life with the sheep in order to obey Yahweh's special call to prophesy to Israel. The phrase “two years before the earthquake” clarifies language about the shaking of the earth elsewhere in the book (8:8; 9:1, 5). Thus the intention of the superscription is to demonstrate that Amos's words about the shaking of the earth were actually fulfilled in the earthquake that subsequently occurred.
The report of Yahweh's roaring and thundering from Zion/Jerusalem (v. 2) portrays Yahweh in the circumstances of a theophany (a technical term for a personal epiphany or appearing of a deity). Such language is characteristically used concerning Yahweh's thundering voice in a theophany (Pss 18:13; 46:6; 104:7; Isa 30:30). Moreover, 1:2 portrays Yahweh's dwelling place as Jerusalem. Nowhere else in the book is that said. Thus this verse supplies an important theological claim that colors our interpretation of the rest of the book: it is the God who dwells in Jerusalem who sends judgment upon Israel.