See the margin. Before, when the Philistines injured him he was in covenant with the Timnathites through his marriage and by the rites of hospitality, for which reason he went off to Ashkelon to take his revenge Judges 14:19. But now the Philistines themselves had broken this bond, and so he was free to take his revenge on the spot.
Related Commentaries of Judges 15:3
Judges 15:3
3 And Samson said concerning them, Now shall I be more blameless than the Philistines, though I do them a displeasure.