6 And the number of them that lapped, putting their hand to their mouth, were three hundred men: but all the rest of the people bowed down upon their knees to drink water.
For the same reason was it that when Gideon was about to overcome the Midianites, he commanded three hundred men to take pitchers, and to hold lighted torches inside the pitchers, and trumpets in their right hands. Our predecessors have preserved the explanation received from the apostles, that the pitchers are our bodies, fashioned of clay, which do not know fear if they burn with the fervor of the grace of the Spirit, and bear witness to the passion of the Lord Jesus with a loud confession of the voice. Who, then, can doubt the divinity of the Holy Spirit, since where the grace of the Spirit is, there the manifestation of the divinity appears. By this evidence we infer not a diversity but the unity of the divine power. For how can there be a severance of power, where the effect of the working in all is one? Neither can there be the grace of the sacraments where there is no forgiveness of sins. What, then, is that fire? Not certainly one made up of common twigs or roaring with the burning of the reeds of the woods, but that fire which improves good deeds like gold and consumes sins like stubble. This is undoubtedly the Holy Spirit, who is called both the fire and light of the countenance of God: light as we said above: “The light of your countenance has been sealed upon us, O Lord.” What is, then, the light that is sealed, but that of the seal of the Spirit, believing in whom, “you were sealed,” he says, “with the Holy Spirit of promise.” And as there is a light of the divine countenance, so, too, does fire shine forth from the countenance of God, for it is written: “A fire shall burn in his sight.” For the grace of the day of judgment shines beforehand, that forgiveness may follow to reward the service of the saints. O the great fullness of the Scriptures, which no one can comprehend with human genius! O greatest proof of the divine unity! For how many things are pointed out in these two verses!
Limiting one’s intake of water helps a great deal to obtain temperance. This was well understood by the three hundred Israelites accompanying Gideon just when they were preparing to attack Midian.
Dogs are commendable, not abominable. They observe fidelity toward their master, and before his house they bark against enemies. He has not simply said “of dogs” but “of your dog.” Nor are their teeth praised, but their tongue is: for it was not indeed to no purpose, not without a great mystery, that Gideon was bidden to lead those alone who should lap the water of the river like dogs. Of such sort not more than three hundred among so great a multitude were found. In this number is the sign of the cross because of the letter T [tau], which signifies three hundred in the Greek numeral characters.
Dogs should not always be taken in an evil sense; otherwise the prophet would not blame “dogs not able to bark and loving to dream.” Doubtless they would be praiseworthy dogs if they both knew how to bark and loved to watch. And certainly those three hundred men—a most sacred number according to the letter of the cross10—would not have been chosen to win the victory because they lapped water as dogs do, unless some great mystery were signified. Good dogs watch and bark to protect their house and their master, their flock and their shepherd. Finally, even here in the praises offered by the church, when a selection is made from this prophecy, it is the tongue of dogs that is mentioned, not their teeth.
And they were brought to the river to drink the waters; and whoever drank the waters with bended knees were removed from the struggle of war. For by the waters is designated the doctrine of wisdom, but by the unbended knee righteous conduct. Therefore those who are reported to have bent their knees while drinking the water retired from the strife of battles, having been forbidden because Christ proceeds to battle against the enemies of the faith with those who, when they drink the streams of doctrine, do not distort the uprightness of their actions. For all are said at that time to have drunk the water, but not all [are said] to have stood with unbended knee. And those who bent their knees while they were drinking the waters were rejected because, as the apostle witnesses, “It is not the hearers of the law who are just before God, but the doers of the law will be justified.” For since weakness of conduct is, as we have said, signified by this very bending of the knees, it is rightly said again by Paul: “Lift up the hands that droop and the feeble knees and make straight steps with your feet.” Therefore those who proceed under Christ as their leader to battle, are those who exhibit in their conduct that which they profess with their mouth, who drink spiritually the streams of doctrine and yet are not carnally distorted by wicked works.
Just as the six hundred years of life which Noah completed prior to entering the ark designate the perfection of faith and confession of those who approach the church’s sacraments of heavenly grace and perpetual reward, so also does the three hundred and fifty years that he lived after the great flood19 typify the perfection of those who, having received the sacraments of life, zealously and faithfully serve the Lord until death. For we say that three hundred, because it is denoted in Greek by the letter tau, which is written in the shape of a cross, most aptly signifies those who resolve not to glory except in the cross of our Lord Jesus Christ. Hence Gideon, at the Lord’s command and with his assistance, conquered the innumerable army of the Midianites with three hundred men, thus teaching figuratively that by faith in the Lord’s cross we will be victorious in the wars waged against us both by this world and by our own vices.
[AD 397] Ambrose of Milan on Judges 7:5-7