Charles Ellicott Commentary 1 Samuel 13:6

"When the men of Israel saw that they were in a strait (for the people were distressed), then the people did hide themselves in caves, and in thickets, and in rocks, and in coverts, and in pits." — 1 Samuel 13:6 (ASV)

Saw that they were in a strait. —It was evidently no ordinary Philistine foray or invasion which the Israelites had to resist. The tradition preserved by Josephus tells us that a host of foreign allies had joined the Phoenician armies in this war. This accounts for the great numbers alluded to in the text: People as the sand which is on the sea shore in multitude (1 Samuel 13:5). The hearts of the still undisciplined Hebrews sank at the news of such an invasion.

And in high places.—The word in the original Hebrew is not the same as the one usually rendered “high places” for prayer and sacrifice. The word here signifies towers. It is the same word which in Judges 9:46; Judges 9:49 is translated “a hold.” In the Speaker’s Commentary it is suggested that it was applied to a particular kind of tower which was the work of the old Canaanite inhabitants, and which remained as ruins in the time of Saul.