David, having settled the courses of these Levites that were to attend the priests in their ministrations, proceeds, in this chapter, to put those into a method that were appointed to be singers and musicians in the temple. Here is, I. The persons that were to be employed, Asaph, Heman, and Jeduthun (Ch1 25:1), their sons (Ch1 25:2-6), and other skilful persons (Ch1 25:7). II. The order in which they were to attend determined by lot (v. 8-31).