I Chronicles 6:33 Midrash

וַאֲחֵיהֶ֖ם הַלְוִיִּ֑ם נְתוּנִ֕ים לְכָ֨ל־עֲבוֹדַ֔ת מִשְׁכַּ֖ן בֵּ֥ית הָאֱלֹהִֽים׃

And their brethren the Levites were appointed for all the service of the tabernacle of the house of God.

Read midrashic interpretation of I Chronicles 6:33: and classical rabbinic exegesis.