The middle watch - The old Jewish division of the night was three watches of four hours each. They are alluded to in Exodus 14:24; 1 Samuel 11:11; Psalm 63:6; Psalm 90:4; Psalm 119:148; Psalm 130:6; Lamentations 2:19. After the Jews fell under the power of the Romans, they used the Roman division of four watches of three hours each Matthew 14:25; Mark 13:35.

"The beginning" of the watch would be about eleven o'clock at night.

So Gideon, and the one hundred men that were with him,.... Which was one of the three companies his army was divided into, and which company he had the command of particularly:

came unto the outside of the camp, in the beginning of the middle watch; the second watch, for the night was divided into three watches; for though in later times there were four watches, among the Romans (h), and which the Jews received from them; hence in the New Testament we read of the fourth watch; yet in earlier times, with the Jews and other eastern nations, there were but three watches, as affirmed by Jarchi and Kimchi on the place: and very wisely did Gideon fix on this watch for the time of his coming; for had he come at the first watch, many as yet might not have been in bed, or at least not fallen asleep; and had he come in the third watch, many might have been awake out of their sleep, and others up; but he took this time, a little after midnight, in the dead of the night, when the whole army was fast asleep:

and they had but newly set the watch; the first watch were just gone off, and the second were placed in their room; but since such an observation seems in a good measure unnecessary, for as Gideon came in the beginning of the watch it must in course be newly set; rather the words may be rendered, "in raising they raised up the watch" (i); that is, Gideon and his men did it by their approach; and they might call to them on purpose to give the alarm to the army, who upon that would at once hear the sound of the trumpets, and the clattering of the pitchers, and see the torches burning, to their great surprise:

and they blew the trumpets, and brake the pitchers that were in their hands; as soon as they came up to the watch and had raised them; this did Gideon and his hundred men.

(h) Liv. Hist. l. 36. c. 24. "Suidas in. voce" "et in voce" (i) "suscitando suscitaverunt custodes", Pagninus, Montanus.

Gideon then proceeded with the 100 who were with him, i.e., the company which was led by himself personally, to the end of the hostile camp, at the beginning of the middle watch, i.e., at midnight ראשׁ is an accusative defining the time: see Ges. 118, 2, and Ewald, 204, a. The only other watch that is mentioned in the Old Testament beside the middle night-watch, is the morning night-watch (Exodus 14:24; 1 Samuel 11:11), from which it has been correctly inferred, that the Israelites divided the night into three night-watches. The division into four watches (Matthew 14:25; Mark 6:48) was first adopted by the Jews from the Romans. "They (the Midianites) had only (just) posted the watchmen (of the middle watch)," - a circumstantial clause, introduced to give greater distinctness to the situation. When the first sentries were relieved, and the second posted, so that they thought they might make quite sure of their night's rest once more, Gideon and his host arrived at the end of the camp, and, as we must supply from the context, the other two hosts at two other ends of the camp, who all blew their trumpets, breaking the pitchers in their hands at the same time. The inf. abs. נפוץ, as a continuation of the finite verb יתקעוּ, indicates that the fact was contemporaneous with the previous one (see Ewald, 351, c.).

So Gideon, and the hundred men that were with him, came unto the outside of the camp in the beginning of the middle watch; and they had but newly set the watch: and they blew the trumpets, and brake the pitchers that were in their hands.

7:19 Middle watch - That is, of the second watch; for though afterward the night was divided into four watches by the Romans, Matt 14:25, yet in more ancient times, and in the eastern parts, it was divided into three: he chose the dark and dead of the night, to increase their terror by the trumpets, whose sound would then be loudest, and the lamps, whose light would then shine most brightly, to surprise them, and conceal the smallness of their numbers.

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, 2Co 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.