If we wanted to remodel a church, we’d hire a general contractor as project manager, and he’d hire the various carpenters, plumbers, electricians, and other craftsmen to do the work.
Not Josiah. When he sets out to repair the temple, he calls on the musicians.
Commenting on 2 Chronicles 34:12-13, William Johnstone notes that Levitical musicians from Merari and Kohath “supervised the whole range of works of reconstruction and renovation in the Temple” (2.238).
We could also put it this way: It’s superficial to think that the temple is made of stone, gold, and cedar wood. Fundamentally, it’s made of people and, specifically, of singers. Restoring the temple means storing a house of song.