John Gill's Bible Commentary Ver. 5. And when Saul saw the host of the Philistines , etc.] From the mountains of Gilboa, where he had pitched his camp: he was afraid, and his heart greatly trembled ; on sight of the numbers of them, and thinking perhaps of the death of Samuel, and of the loss of David; who was now among the Philistines, and might possibly fight against him, and for the Philistines, of which he might be informed; however, he was not with him, and his conscience might accuse him of various sins he had been guilty of, for which he might fear the Lord would now reckon with him.
Matthew Henry Commentary
Verses 1-6 - David could not refuse Achish without danger. If he promise assistance, and then stood neuter, or went over to the Israelites, he would behave with ingratitude and treachery. If he fought agains Israel, he would sin greatly. It seemed impossible that he should ge out of this difficulty with a clear conscience; but his evasive answer intended to gain time, was not consistent with the character of a Israelite indeed. Troubles are terrors to the children of disobedience In his distress, Saul inquired of the Lord. He did not seek in faith but with a double, unstable mind. Saul had put the law in force agains those that had familiar spirits, Ex 22:18. Many seem zealous against sin, when they are any way hurt by it, who have no concern for the glory of God, nor any dislike of sin as sin. Many seem enemies to sin in others, while they indulge it in themselves. Saul will drive the devil out of his kingdom, yet harbours him in his heart by envy an malice. How foolish to consult those whom, according to God's law, he had endeavoured to root out!
Original Hebrew וירא7200 שׁאול7586 את853 מחנה4264 פלשׁתים6430 וירא3372 ויחרד2729 לבו3820 מאד׃3966