Albert Barnes Commentary 1 Samuel 13:17

"And the spoilers came out of the camp of the Philistines in three companies: one company turned unto the way that leadeth to Ophrah, unto the land of Shual;" — 1 Samuel 13:17 (ASV)

The spoilers—"The devastator"—is the same word used for the destroying Angel in Exodus 12:23. This verse describes the system the Philistines adopted to subjugate the Israelites. From their central camp at Michmash, they sent out three bands to kill, lay waste, and destroy.

One band took a northerly direction toward Ophrah (five miles east of Bethel, identified with “Ephrain” in 2 Chronicles 13:19 and the modern “Taiyibeh”) and toward the land of Shual, possibly the same as Shalim (1 Samuel 9:4). The second went westward to Beth-horon, and the third traveled eastward through the unknown valley of Zeboim toward the wilderness, that is, the Jordan valley near Jericho.