1 Samuel 13:4

And Israel rose up against the Philistines. With the word ministers pressing on, either to crush the enemies of their virtue, or with the trumpet of lofty preaching to rouse their neighbors to the path of virtue, the spirits of the listeners are aroused to undergo the spiritual struggle, to investigate, avoid, and overcome the wiles of the airborne powers.

Therefore the people cried after Saul in Gilgal, etc. As the zeal for performing virtues increases in the good, so also increases the zeal of the unclean spirits to hinder and break the same virtue; who, seeing the friends of the faithful risen against them, strive to assail these hills of various snares and deceptions with their forces: and as if they ascend in chariots, the Philistines, when numerous cohorts of gentiles, or of perfidious synagogues, or assemblies of heretics, ascend with the most wicked enemy against the army of virtue: they sit on horses, when they compel the hearts of the perverse, constricted by the bridle of error, to oppose the faithful: they proceed on foot, when they lay traps for themselves. Of which it is aptly subjoined:

6. When the garrison of the Philistines was struck, Saul sounds the trumpet, and after Saul the people shout: because holy preachers proclaim the heard virtues of the elect, and inflame the hearts of their subjects to the example of good work. To sound the trumpet is both to announce victory and to rouse the minds of others by the example of the victors to the purpose of spiritual warfare. For the people to shout after Saul is to undertake the daring of great devotion from having heard the preaching. At this point it should be noted that Jonathan struck the garrison of the Philistines, but Saul, sounding the trumpet, claimed that he himself had struck that same garrison. Because indeed the triumphs of the elect preachers are credited with the fact that hidden adversaries are overcome by their subjects. But as often as we conquer some enemies, it is necessary that we prepare ourselves for the struggles of overcoming others. For Almighty God, because He rewards His elect more abundantly, always wills them to stand in battle, so that they themselves may always be able to prepare for themselves the goods of an eternal reward. For this reason also, when the people are said to have shouted after Saul, it is added: (Verse 5.) And the Philistines gathered together to fight against Israel: thirty thousand chariots, and six thousand horsemen, and the rest of the common people like the sand which is on the seashore in great multitude.