4,000 are to be gatekeepers, and 4,000 are to praise the LORD with the instruments I have made for giving praise.”
Here we have, I. The crown entailed, according to the divine appointment, Ch1 23:1. David made Solomon king, not to reign with him, or reign under him, but only to reign after him. This he did, 1. When he was old and full of days. He was but seventy years old when he died, and yet he was full of days, satur dierum - satisfied with living in this world.
Commenting on 1 Chronicles 23:1-23
Moreover four thousand were porters,.... At the east, north, and south gates of the temple, in their turns: and four thousand praised the Lord with the instruments; were singers in the temple, which in all made up 38,000: which I made, said David, to praise therewith; which instruments he devised and ordered to be made to praise the Lord with; see Ch2 29:26.
praised the Lord with the instruments which I made--David seems to have been an inventor of many of the musical instruments used in the temple (Amo 6:5).