Charles Ellicott Commentary Judges 20:21

"And the children of Benjamin came forth out of Gibeah, and destroyed down to the ground of the Israelites on that day twenty and two thousand men." — Judges 20:21 (ASV)

Came forth out of Gibeah. —The whole armed force of the tribe had therefore assembled to save the wicked town from assault. Like many of the towns of Palestine (as their names indicate), it was on a hill, and therefore easily defensible against the very imperfect siege operations of the ancients.

Destroyed down to the ground — i.e., laid them dead on the ground, as in Judges 6:25.

Twenty and two thousand men. —This immense slaughter shows the extraordinary fierceness of the battle. The Benjamite force must have nearly killed a man apiece.