Refers to the singers treated of in 1 Chronicles 9:14-16 : And these (above mentioned) are the minstrels, heads of Levitical families; in the Temple cells (they lived), exempt from all other charge; for day and night they were over them in the work. The Hebrew is, harsh, and perhaps corrupt, but the meaning seems to be clear. It is hardly meant that the service of song in the Temple was uninterrupted (comp. Revelation 4:8), but only that the choristers were under obligation to perpetually recurring service.
They were employed in that work. — Rather, They were over them in the work. They — that is, the leaders for the time being — lived, like the chief warders, in the Temple cells, presiding continually over the guilds of singers.