Albert Barnes Commentary Judges 3:19

"But he himself turned back from the quarries that were by Gilgal, and said, I have a secret errand unto thee, O king. And he said, Keep silence. And all that stood by him went out from him." — Judges 3:19 (ASV)

Gilgal was in the immediate neighborhood of Jericho (Judges 2:1), where doubtless Eglon held his court at this time (Judges 3:13).

Quarries — Some interpret the original word in its common meaning of carved images or idols (see the margin).