By burning Samson’s wife and her father to death, the Philistines bring upon his wife the very punishment she thought she would escape by revealing the solution to the riddle in Judges 14 (see Judges 14:15). They thereby fulfill their earlier threat.
6 Then the Philistines said, “Who has done this?” And they said, “Samson, the son-in-law of the Timnite, because he has taken his wife and given her to his companion.” And the Philistines came up and burned her and her father with fire.