וְה֣וּא שָׁ֗ב מִן־הַפְּסִילִים֙ אֲשֶׁ֣ר אֶת־הַגִּלְגָּ֔ל וַיֹּ֕אמֶר דְּבַר־סֵ֥תֶר לִ֛י אֵלֶ֖יךָ הַמֶּ֑לֶךְ וַיֹּ֣אמֶר הָ֔ס וַיֵּֽצְאוּ֙ מֵֽעָלָ֔יו כָּל־הָעֹמְדִ֖ים עָלָֽיו׃
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.
Metzudat Zion on Judges
Idols: the place where they carve out the face of the stone as in "the sons of Shlomo carved."