First Book of Paralipomenon (Author Compiled by Isaias and Esdras from records of Nathan, Gad, Addo, Ahias, Jehu and others.)
23:32And let them keep the observances of the tabernacle of the covenant, and the ceremonies of the sanctuary, and the charge of the sons of Aaron their brethren, that they may minister in the house of the Lord.
Original from Project Gutenberg - Massive cleanup of OCR problems and editing done locally.