Joel 3:6

The children also of Judah, the Jews who dwelt in the land, and the children of Jerusalem, the citizens of Jerusalem; or perhaps the young ones, boys and girls, as Joel 3:3, both of city and country. Ye; Tyrians, Zidonians, and Philistines, though neighbours, and oftentimes befriended by the Jews, yet you have done this. Sold unto the Grecians; or sons of Grecians, who either employed them as slaves in Greece, or else sold them to other nations for slaves. That ye might remove them far from their border; that there might be no hope to these poor captives ever to return to their country, nor fear to the Tyrians and Zidonians of being called to account for the injury by them it was done unto. Amos 1:6,9, mentions this sin of the Philistines, and God's displeasure at it.