1 Chronicles 25:1

Moreover, David and the captains of the army set apart for the service certain of the sons of Asaph, of Heman, and of Jeduthun, who were to prophesy with harps, with stringed instruments, and with cymbals. The number of those who did the work according to their service was:

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: