Moreover David and the captains of the host separated to the service of the sons of Asaph, and of Heman, and of Jeduthun, who should prophesy with harps, with psalteries, and with cymbals: and the number of the workmen according to their service was: (1 Chronicles 25:1)
Chapter 25 lists the 24 classes of singers. These musicians formed an important group and played a significant part in the Temple services.
Captains of the host.
That is, chiefs or leaders of the service—the ones mentioned in ch. 24:6.
Separated to the service.
That is, they set apart for the Temple service some of the sons of Asaph, and Heman, and Jeduthun, three classes of musicians.
Prophesy with harps.
Compare 1 Sam. 10:5. The musicians in the performance of their sacred duties in public worship are described as being under the inspiration of the Spirit of God and thus said to “prophesy” (see 1 Chron. 25:3).