Two ends of this shout Caesar indicated (book 3 of the Civil War): “Nor,” he says, “was it instituted of old in vain, that the signals should sound together on every side, and that all should raise a shout — by which things they judged both that the enemy is terrified and that their own men are incited.” Whence Gellius (book 1, ch. 11): “that spirits may be roused and whetted, horns and clarions are set in motion.” And a physical cause can be given from those things which the Philosopher [Aristotle] disputes about the voice (Problems, section 11); just as [there is a reason] why skilled leaders would sometimes make a conjecture about the battle’s outcome from that shout — “the shout,” says Livy (book 4), “was the first indication of which way the matter would incline: more excited and more frequent, raised by the enemy (the Volscian), [it foretold victory]; but by the Romans, dissonant, uneven, sluggish, often repeated, it betrayed the panic of their spirits.” Nor unlike[ly does] Plutarch [treat it] in the Crassus disaster. But God and Joshua seem to have had the same ends in the Israelites’ shout — yet not these alone. First, because the enemies were to be utterly terrified and stunned with fear, so that thus they would not even draw a single sword against the Israelites, and not even one of these [Israelites] should be even most lightly hurt. Secondly, the spirit of the Israelites was to be incited, that they might rush most eagerly into the collapsing city, fear nothing at all, and put to slaughter whatever they met. Thirdly, that shouting was, as it were, a certain public prayer to God, that he might now in very deed fulfill what he had deigned to promise. Fourthly, it was a testimony of their utmost faith and confidence in God, while they professed themselves…
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…[while they professed themselves] to doubt nothing about this city’s destruction, while they did even these light and easy things which he had commanded. Fifth: it was an index of a spirit prepared and exulting, as if they were already gaining a most certain victory; and so they sang thanks to God, and the enemy’s “penalty,” now most joyful. Sixth: it was a Symbol of other things, concerning which below.