וְהִנֵּ֡ה אֲמַרְיָ֣הוּ כֹהֵן֩ הָרֹ֨אשׁ עֲלֵיכֶ֜ם לְכֹ֣ל דְּבַר־יְהוָ֗ה וּזְבַדְיָ֨הוּ בֶן־יִשְׁמָעֵ֜אל הַנָּגִ֤יד לְבֵית־יְהוּדָה֙ לְכֹ֣ל דְּבַר־הַמֶּ֔לֶךְ וְשֹׁטְרִ֥ים הַלְוִיִּ֖ם לִפְנֵיכֶ֑ם חִזְק֣וּ וַעֲשׂ֔וּ וִיהִ֥י יְהוָ֖ה עִם־הַטּֽוֹב׃ (פ)
Sifrei Devarim
"and bailiffs for your tribes": wielders of the lash, viz. (II Chronicles 19:11) "and the Levite bailiffs before you," and (Nechemiah 8:11) "and the Levites silenced all the people."
Sifrei Devarim
R. Yehudah says: Whence is it derived that one is appointed over all? From "shall you appoint for yourself."