I Chronicles 6:39

Asaph - This person, with Heman, the sons of Kora, Ethan, Jeduthun, etc., are celebrated in these books, and in the Psalms, for their skill in singing, and the part they performed in the public worship of God. It is very likely that their singing was only a kind of recitative or chanting, such as we still find in the synagogues. It does not appear that God had especially appointed these singers, much less any musical instruments, (the silver trumpets excepted), to be employed in his service. Musical instruments in the house of God are, at least under the Gospel, repugnant to the spirit of Christianity, and tend not a little to corrupt the worship of God. Those who are fond of music in the theater are fond of it in the house of God when they go thither; and some, professing Christianity, set up such a spurious worship in order to draw people to hear the Gospel! This is doing evil that good may come of it; and by this means, light and trifling people are introduced into the Church of Christ, and when in, are generally very troublesome, hard to be pleased, and difficult to be saved.

his brother Asaph--They were brothers naturally, both being descended from Levi, as well as officially, both being of the Levitical order.

But Aaron and his sons,.... Those that descended from him, though of the same tribe of Levi were all priests: and they offered upon the altar of burnt offerings; the daily sacrifice, and all the offerings of the people brought to them: and on the altar of incense; they burnt incense night and morning: and were appointed for all the work of the place most holy; such as were high priests of the line of Eleazar, whose work it was to go into the most holy place once a year: to make atonement for all Israel, according to all that Moses the servant of God commanded; in Lev 16:1 which see; and on mention of this, a list of the high priests from Aaron, in the line of Eleazar, is given, to the times of Solomon, in the four following verses, just in the same order as in Ch1 6:4.

But Aaron and his sons,.... Those that descended from him, though of the same tribe of Levi were all priests: and they offered upon the altar of burnt offerings; the daily sacrifice, and all the offerings of the people brought to them: and on the altar of incense; they burnt incense night and morning: and were appointed for all the work of the place most holy; such as were high priests of the line of Eleazar, whose work it was to go into the most holy place once a year: to make atonement for all Israel, according to all that Moses the servant of God commanded; in Lev 16:1 which see; and on mention of this, a list of the high priests from Aaron, in the line of Eleazar, is given, to the times of Solomon, in the four following verses, just in the same order as in Ch1 6:4.

Though Joseph and Judah shared between them the forfeited honours of the birthright, yet Levi was first of all the tribes, dignified and distinguished with an honour more valuable than either the precedency or the double portion, and that was the priesthood. That tribe God set apart for himself; it was Moses's tribe, and perhaps for his sake was thus favoured. Of that tribe we have an account in this chapter. I. Their pedigree, the first fathers of the tribe (Ch1 6:1-3), the line of the priests, from Aaron to the captivity (Ch1 6:4-15), and of some other of their families (Ch1 6:16-30). II. Their work, the work of the Levites (v. 31-48), of the priests (Ch1 6:49-53). III. The cities appointed them in the land of Canaan (v. 54-81).

6:39 Asaph wrote several psalms (Pss 50; 73–83).