1Sam 14:36

“This has been sufficiently explained above, but because he desires to strike the Philistines in the night until the day dawns, this surely suggests that, lest demons be able to cause harm in the future, they must now be driven out and destroyed from the hearts of sinners. Indeed, this life is called night when it is compared to eternal life. For whoever has been able to worthily contemplate that life, in comparison with it, whatever appears bright here is judged to be the darkness of night. But that day dawns when, at the end of this life, it opens itself to the souls of the elect. For at its departure from the body, the elect soul sees eternity dawning upon it, because it did not gaze upon the light of the present age, regarding it as darkness. But what does it mean when it is said: "And let us not leave of them a man"? But every Philistine man must be destroyed; every little one cannot be destroyed at all. For no one is without sin, except God alone. Therefore the "men" are capital crimes and principal vices. But they are designated by the name of men, that is, of strong ones, when they subject the hearts of sinners to themselves. Rightly therefore it is said: "Let us not leave of them a man," because converted sinners, by the counsel of holy preachers, abandon all their strong sins and vices, but they cannot have no sin or vice at all. They can guard against crimes, but they cannot avoid all sins. They can extinguish vices, but they are unable to prevent themselves from being in some way struck by any of them. He says therefore: "Let us not leave of them a man," because the preachers of holy Church command us to uproot our vices; but while they slay the strong and principal ones in us, they are unable to bring it about that certain of them do not in some way live through a faint stirring. And adding concerning the obedience of the people, he says: (Verse 36.) "The people said: Do whatever is good in your eyes." The eyes of preachers are the gaze of reason. He who is entrusted to the judgment of a teacher is therefore rightly said to say to him: "Do whatever is good in your eyes." As if to say: We who distrust the illumination of our own reason entrust to the light of your reason what we judge to be lacking in ourselves. But what Saul said, "Let us rush upon the Philistines," can be understood to mean that he did not put forward a deliberated decision, but by saying this, he was consulting whether they should rush upon the Philistines. But the fact that the people quickly gave their assent suggests what we observe, that some within the holy Church approve the words of their superiors before they understand them. ...”

“And Saul said, "Let us go down after the Philistines by night," etc. Saul, planning to attack the Philistines by night and to destroy them completely, consults the oracle of the Lord but is not answered; and seeking the cause of the sin, he discovers it by lot and adjudicates Jonathan, who confesses, to death; however, since he had brought great salvation to Israel, the people rescue him from the judgement of death. Good leaders often desire to expel all the snares of demons and to eradicate the tares sown among the good seed from the field of this world if possible, yet they receive no answer from the Lord through the Scriptures that this can be done; upon seeking the cause, they hear nothing more than that human frailty and ignorance are to blame; for even the most eminent teachers and leaders of the faithful, in the good works they do, cannot stand immune to the suggestions of sin, but all offend in many ways; nevertheless, lest they suffer eternal death because of these, they are helped by the merits of the good deeds they have done and by the prayers of the Churches they fought to strengthen.”