Judges 7:16-19

16Then he divided the three hundred men into three companies, and he put a trumpet into every man’s hand, with empty pitchers, and torches inside the pitchers.

17And he said to them, “Look at me and do likewise; watch, and when I come to the edge of the camp you shall do as I do:

18When I blow the trumpet, I and all who are with me, then you also blow the trumpets on every side of the whole camp, and say, ‘The sword of the Lord and of Gideon!’ ”

19So Gideon and the hundred men who were with him came to the outpost of the camp at the beginning of the middle watch, just as they had posted the watch; and they blew the trumpets and broke the pitchers that were in their hands.