The sense is, “And they (the three hundred) took the victuals and trumpets of the people (all the people of Judges 7:7) into their hands.” so that each of the three hundred should have a trumpet and a pitcher.
Related Commentaries of Judges 7:8
Judges 7:8
8 So the people took victuals in their hand, and their trumpets: and he sent all the rest of Israel every man unto his tent, and retained those three hundred men: and the host of Midian was beneath him in the valley.