v1: Amos' final vision; the Lord Himself, standing by the altar. His words are not comforting, but severe.
v2-4: God's omniscience, for none can hide from Him; see Ps 139. In the Psalm, God's omniscience promises blessing, here it brings judgment.
v5-6: God's greatness; seek Him and live, for "the Lord is His Name." Israel should not have to be reminded of the true nature of the true God. This God is the One they must return to, or the One who would judge them.
v7: Israel, just like the nations; should God not treat them like other nations?
Philistines from Kaphtor, probably Crete, a sea-faring nation. There is some historic evidence of a natural disaster in Crete, from which some escaped, presumably to Philistia.
v8-10: God's mercy and justice; His mercy tempers His justice; later His mercy triumphs over judgment. The sinful kingdom will be judged, but the house of Jacob shaken, and not utterly destroyed. Israel will be sifted among the nations; and we still see this today, as Jews live in almost every nation in the world.
God will judge all the sinners, but the righteous will be preserved, like a stone in a sieve; He will never slay the righteous with the wicked. His eternal promises for Israel remain.
Note too the complacency of the wicked, "Disaster will not overtake or meet us," yet these words give false hope.
v11-15: Clear promises of Israel's final restoration; the tabernacle of David rebuilt. Israel will possess the land, even the land of Edom; Gentile nations will be called by His Name. The people will be restored to the land, and enjoy abundant fruitfulness.
Never again will the people suffer exile from their land.
Part of this section is quoted in Acts 15.16-18; at the Council of Jerusalem, the apostle James teaches that Amos' words prophesy blessing on all nations, as the Gentiles receive the good news of Jesus.
No longer is the blessing restricted to one nation. And no longer oculd that one nation claim any superiority over other nations; see comment on 1.1-2.
It is significant that Amos opens with judgment on all the nations including Judah and Israel; now he closes with blessing on all nations, including Judah and Israel.