That they should offer holocausts to the Lord upon the altar of holocausts continually, morning and evening, according to all that is written in the law of the Lord, which he commanded Israel.

to cause to ascend burnt-offerings to Jehovah, on the altar of burnt-offering continually, morning and evening, and for all that is written in the law of Jehovah, that He charged on Israel.

To give burned offerings to the Lord on the altar of burned offerings morning and evening, every day, as it is ordered in the law of the Lord which he gave to Israel;

so that they could offer holocausts to the Lord upon the altar of holocausts continually, morning and evening, according to all that was written in the law of the Lord, which he instructed to Israel.

Upon the altar of the burnt offering - The original altar of burnt-offering Exodus 27:1-8 continued at Gibeon with the tabernacle 2-Chronicles 1:3, 2-Chronicles 1:5. David must have erected a new altar for sacrifice at Jerusalem 1-Chronicles 16:1. The sacrifices commanded by the Law were, it appears, offered at the former place; at the latter were offered voluntary additional sacrifices.

To offer burnt offerings unto the Lord,.... Which was the work of the priests only to do:
upon the altar of burnt offering continually morning and evening; the lambs of the daily sacrifice, which were a burnt offering, and only to be offered on the brasen altar at the tabernacle:
and to do according to all that is written in the law of the Lord, which he commanded Israel; with regard to them, and all other sacrifices, see Exodus 29:38.

continually morning and evening--as the law enjoined (Exodus 29:38; Numbers 28:3, Numbers 28:6).
and do according to all that is written in the law--(See Numbers. 28:1-31). Thus, in the time of David, the worship was performed at two places, where the sacred things that had been transmitted from the age of Moses were preserved. Before the Ark in Jerusalem, Asaph and his brethren officiated as singers, Obed-edom and Hosah served as doorkeepers, and Benaiah and Jahaziel blew the trumpets. While at the tabernacle and burnt offering in Gibeon, Heman and Jeduthun presided over the sacred music, the sons of Jeduthun were door keepers, and Zadok, with his suite of attendant priests, offered the sacrifices.

Which he commanded Israel - These must be kept up; because however in their own nature they were inferior to prayer and praise, yet as they were types of the mediation of Christ, the observance of them was of mighty importance.