Albert Barnes Commentary Judges 15:4

"And Samson went and caught three hundred foxes, and took firebrands, and turned tail to tail, and put a firebrand in the midst between every two tails." — Judges 15:4 (ASV)

Foxes - Rather, “jackals,” which are still very common in Palestine, especially about Joppa and Gaza. 1 Samuel 13:17, Joshua 15:28, and Joshua 19:3 are indications of the abundance of foxes or jackals giving names to places, especially in the country of the Philistines.

It is consistent with Samson’s character, and agrees with the incident about the lion, that he was an expert hunter.

Ovid relates a very curious custom at Rome of letting loose foxes with lighted torches fastened to their tails in the circus at the Cerealia, in commemoration of the damage once done to the standing grain by a fox which a rustic had wrapped in hay and straw and set on fire, and which, running away, put the grain-fields in a blaze. This custom, which may have had a Phoenician origin, is a curious illustration of the narrative.