16 And he divided the 300 men into three companies and put trumpets into the hands of all of them and empty jars, with torches inside the jars. 17 And he said to them, "Look at me, and do likewise. When I come to the outskirts of the camp, do as I do. 18 When I blow the trumpet, I and all who are with me, then blow the trumpets also on every side of all the camp and shout, 'For the Lord and for Gideon.'" 19 So Gideon and the hundred men who were with him came to the outskirts of the camp at the beginning of the middle watch, when they had just set the watch. And they blew the trumpets and smashed the jars that were in their hands. 20 Then the three companies blew the trumpets and broke the jars. They held in their left hands the torches, and in their right hands the trumpets to blow. And they cried out, "A sword for the Lord and for Gideon!"
Matthew Henry's Commentary on Judges 7:16-20
Commentary on Judges 7:16-22
(Read Judges 7:16-22)
This method of defeating the Midianites may be alluded to, as exemplifying the destruction of the devil's kingdom in the world, by the preaching of the everlasting gospel, the sounding that trumpet, and the holding forth that light out of earthen vessels, for such are the ministers of the gospel, 2 Corinthians 4:6,7. God chose the foolish things of the world to confound the wise, a barley-cake to overthrow the tents of Midian, that the excellency of the power might be of God only. The gospel is a sword, not in the hand, but in the mouth: the sword of the Lord and of Gideon; of God and Jesus Christ, of Him that sits on the throne and the Lamb. The wicked are often led to avenge the cause of God upon each other, under the power of their delusions, and the fury of their passions. See also how God often makes the enemies of the church instruments to destroy one another; it is a pity that the church's friends should ever act like them.