Divrei Hayamim 23:28

כִּ֣י מַעֲמָדָ֞ם לְיַד־בְּנֵ֣י אַהֲרֹ֗ן לַֽעֲבֹדַת֙ בֵּ֣ית יְהֹוָ֔ה עַל־הַֽחֲצֵרוֹת֙ וְעַל־הַלְּשָׁכ֔וֹת וְעַֽל־טׇהֳרַ֖ת לְכׇל־קֹ֑דֶשׁ וּמַֽעֲשֵׂ֔ה עֲבֹדַ֖ת בֵּ֥ית הָאֱלֹהִֽים׃

because their station was at the side of the sons of Aharon for the service of the house of the Lord, in the courts, and in the chambers, and in the purifying of all holy things, and the work of the service of the house of God;