I Chronicles 23:26

Because their office was to wait on the sons of Aaron,.... The priests: for the service of the house of the Lord; to assist them therein, and not to bear burdens as in times past; the Targum is,"wherefore the place of their habitations was by the side of the sons of Aaron, for the worship of the sanctuary of the Lord:" in the courts, and in the chambers, and in the purifying of all holy things, and the work of the service of the house of God; to keep the house, and all the apartments in it, courts and chambers, clean, by sweeping and washing them, and carrying out all the filth thereof made by the sacrifices, and otherwise.

David, having given charge concerning the building of the temple, in this and the following chapters settles the method of the temple-service and puts into order the offices and officers of it. In the late irregular times, and during the wars in the beginning of his reign, we may suppose that, though the Levitical ordinances were kept up, yet it was not in the order, nor with the beauty and exactness, that were desirable. Now David, being a prophet, as well as a prince, by divine warrant and direction, "set in order the things that were wanting." In this chapter we are informed, I. He declared Solomon to be his successor, (Ch1 23:1). II. He numbered the Levites, and appointed them to their respective offices (Ch1 23:2-5). III. He took an account of the several families of the Levites (v. 6-23). IV. He made a new reckoning of them from twenty years old, and appointed them their work (Ch1 23:24-32). And in this he prepared for the temple as truly as when he laid up gold and silver for it; for the place is of small account in comparison with the work.