When Saul saw - He saw from the superiority of his enemies, from the state of his army, and especially from his own state towards God, that he had every thing to fear.

And when Saul saw the host of the Philistines,.... 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.

And when Saul saw the host of the Philistines, he was afraid, and his heart greatly trembled.

28:5 He trembled - Had he kept close to God, he needed not fear all the armies of the Philistines.

28:1-6 David could not refuse Achish without danger. If he promised assistance, and then stood neuter, or went over to the Israelites, he would behave with ingratitude and treachery. If he fought against Israel, he would sin greatly. It seemed impossible that he should get out of this difficulty with a clear conscience; but his evasive answer, intended to gain time, was not consistent with the character of an 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 against 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 and malice. How foolish to consult those whom, according to God's law, he had endeavoured to root out!