1:6 Gaza was the chief city of Philistia as Damascus was of Aram. The particular sin for which God would judge the Philistines was their capture and deportation of whole communities (or people at peace, Heb. shelema), possibly Israelites and or Judahites, to Edom as slaves (cf. Joel 3:4-8).
"The concern of Amos seems to have been the freedom and dignity of persons regardless of their national origin. Sale of such captives for use as slave laborers was to treat precious humans made in the image of God (Gen 1:26-27) as mere commodities. The driving force behind these atrocities was nothing higher than the profit of the mighty.
"Broken treaties have marred the pages of history from ancient to modern times. God has a low tolerance level for those who break treaties, who take away human freedom and dignity, and whose motive is material profit. Such people should brace themselves for the destructive judgment of God."22
1:7-8 Fire (destruction) would overtake the cities of the Philistines and affect everyone from the ordinary citizens to the rulers. Amos mentioned four of the five major cities of Philistia, all except Gath, probably because it had already fallen to enemies (cf. 6:2; 2 Kings 12:17; 2 Chron. 26:6).23Sovereign Yahweh promised to cut off even the remnant of Philistines that remained in Amos' day.24This prophecy was fulfilled during the Maccabean period (169-134 B.C.) when the Philistines passed out of existence.