This is now the third time in chapters 14 and 15 that Samson uses something from the animal world for his purposes. First it was a lion that he killed, from whose carcass he drew honey (Judges 14:5–9). Then it was foxes he caught and used as incendiary missiles in his act of revenge (Judges 15:4–5). Now he uses the jawbone of a donkey to kill a thousand of his enemies. One could say that this is Samson exercising dominion over the animals, but this is in fact a misuse of that dominion.
15 And he found a fresh jawbone of a donkey, and put out his hand and took it, and with it he struck 1,000 men.