Verse 1
1 Chronicles 25:1. And captains — All the princes of Israel, with the priests and the Levites, whom David gathered together (1 Chronicles 23:2) for this very end, that, with their approbation and consent, all these things might be established, who are here fitly called the captains of the host; for the princes were, under David, the chief captains of the militia of the kingdom; and as the Levites are called a host, and the Lord’s host, because of their number and order in holy ministrations, so these priests and Levites were the captains and governors of the rest. Separated — Distributed them into their several ranks: which, though chiefly done by David as a prophet, and by divine direction, yet is imputed in part to the captains of the host, because it was done with their concurrence and approbation. The service — To the service of God, under the conduct of these persons. Who should prophesy — Praise God by singing the psalms of David, and other sacred songs made by themselves, who were prophets, or by other prophets or holy men of God. The number of the workmen according to their service — Although this sacred work of praising God is here termed service, and the persons employed in it workmen, yet it is the greatest liberty and pleasure to be engaged in it. But the expressions intimate that it is our duty to make a business of it, and stir up all that is within us to it; and that in our present state of corruption and infirmity, it will not be done, as it should be done, without labour and struggle. We must take pains with our hearts to bring and keep them to this work, and to engage all that is within us in it. It is probable, Heman, Asaph, and Jeduthun were bred up under Samuel, and had their education in the schools of the prophets, of which he was the founder and president. Then they were pupils, now they come to be masters. Those that would be eminent must begin early and take time to prepare themselves. This good work, of singing God’s praises, Samuel revived and set on foot, but lived not to see it brought to the perfection in which it appears here. Solomon perfects what David began. So David perfects what Samuel began. Let each in their day do what they can for God and his church, though they cannot carry it so far as they would; when they are gone, God can out of stones raise up others, who shall build upon their foundation, and bring forth the top-stone.

Verse 2-3
1 Chronicles 25:2-3. Under the hands of Asaph — Under his oversight and direction. According to the order of the king — In such manner and order as David appointed. The sons of Jeduthun, six — Jeduthun, their father, being included in that number; or Shimei, mentioned 1 Chronicles 25:17.

Verse 5
1 Chronicles 25:5. The king’s seer — Or prophet. Either he was a prophet as well as a singer; or he is thus called because he prophesied, or praised God, in the sense designed 1 Chronicles 25:1. And he is called the king’s seer, because the king took special delight in him; or because he frequently attended the king in his palace, executing his sacred office there, while the rest were employed in the tabernacle. In the words of God — To sing such divine songs as were inspired by God to the prophets or holy men of God. To lift up the horn — To praise God with the sound of a trumpet, or some other musical instrument made of horn, which, being a martial kind of music, might be most grateful to David’s martial spirit: though he was also skilled in other instruments of music which he used in the house of God.

Verse 7
1 Chronicles 25:7. All that were cunning — Who were so skilful that they were able to teach others; and, together with their scholars, made up the four thousand mentioned 1 Chronicles 23:5.

Verse 8
1 Chronicles 25:8. Ward against ward — A course of Levites answerable to one of the priests, upon whom the Levites were to wait in their holy ministrations, 1 Chronicles 23:28. As well the teacher as the scholar — Without any respect to their different ages or abilities.

Verse 9
1 Chronicles 25:9. To Joseph — For the family of Asaph, of which Joseph was. Here that clause, he, his sons, and his brethren were twelve, is to be understood as it is expressed in all the following verses, otherwise they do not make up that number of two hundred and eighty-eight, mentioned 1 Chronicles 25:7.