וַ֠יֹּאמֶר יְחִזְקִיָּ֨הוּ הַמֶּ֤לֶךְ וְהַשָּׂרִים֙ לַלְוִיִּ֔ם לְהַלֵּל֙ לַֽיהוָ֔ה בְּדִבְרֵ֥י דָוִ֖יד וְאָסָ֣ף הַחֹזֶ֑ה וַֽיְהַלְלוּ֙ עַד־לְשִׂמְחָ֔ה וַֽיִּקְּד֖וּ וַיִּֽשְׁתַּחֲוֽוּ׃ (פ)
Moreover Hezekiah the king and the princes commanded the Levites to sing praises unto the LORD with the words of David, and of Asaph the seer. And they sang praises with gladness, and they bowed their heads and prostrated themselves.
Read midrashic interpretation of II Chronicles 29:30: and classical rabbinic exegesis.