John Gill Commentary Judges 20:17

"And the men of Israel, besides Benjamin, were numbered four hundred thousand men that drew sword: all these were men of war." — Judges 20:17 (ASV)

And the men of Israel, beside Benjamin Who did not join them in this affair, but opposed them,

were numbered four hundred thousand men that drew sword : see (Judges 20:9)

all these were men of war ; inured to it, skilful and courageous.