וַיִּשְׁלַ֣ח אַ֠בְשָׁלוֹם אֶת־אֲחִיתֹ֨פֶל הַגִּֽילֹנִ֜י יוֹעֵ֣ץ דָּוִ֗ד מֵֽעִירוֹ֙ מִגִּלֹ֔ה בְּזָבְח֖וֹ אֶת־הַזְּבָחִ֑ים וַיְהִ֤י הַקֶּ֙שֶׁר֙ אַמִּ֔ץ וְהָעָ֛ם הוֹלֵ֥ךְ וָרָ֖ב אֶת־אַבְשָׁלֽוֹם׃
And Absalom sent for Ahithophel the Gilonite, David’s counsellor, from his city, even from Giloh, while he offered the sacrifices. And the conspiracy was strong; for the people increased continually with Absalom.
Read midrashic interpretation of II Samuel 15:12: and classical rabbinic exegesis.