en_tn/1ch/23/30.md

They also stood

"The Levites also stood"

whenever burnt offerings were offered to Yahweh

AT: "whenever the priests offered burnt offerings to Yahweh" (See: rc://en/ta/man/translate/figs-activepassive)

new moon festivals

These holidays marked the beginning of each new month.

A fixed number, assigned by decree, always had to be present before Yahweh

AT: "It was the duty of a certain number of the Levites to always be present in making offerings to Yahweh"