Amos 1:6

Thus saith the LORD; For three transgressions of Gaza, and for four, I will not turn away the punishment thereof; because they carried away captive the whole captivity, to deliver them up to Edom:

In Amos 1–5 the declaration belongs to the series of prophecies condemning the surrounding nations. It declares that punishment for Gaza will not be turned away because its people carried away captive the whole captivity to deliver them up to Edom. Together with Amos 1:9 it points to the invasion of Judah in Jehoram's reign, when the Philistines with Tyre seized goods and sold people from Judah and Jerusalem to be taken far from their land. It teaches that nations are accountable for their conduct and will be punished when they fail to live up to the light and knowledge they have received.