Neh 12:26

“And at the dedication of the wall of Jerusalem,.... In which many priests and Levites assisted, and seems to be the reason of the above account of them; the dedication of the wall takes in the whole city, gates, and houses, Neh 12:30, and if a new house was to be dedicated, much more a new city, and especially the holy city, in which stood the temple of the Lord, see Deu 20:5, this dedication was made by prayer and songs of praise, as follow, and no doubt by sacrifices, and was kept as a festival; and indeed, according to the Jewish writers (q), it was annually observed on the seventh of Elul, or August; it was on the twenty fifth of that month that the wall was finished, Neh 6:15, but the gates were not set up, and all things for the dedication were not ready till Elul, or August, following; and then all being finished, they made and served the seventh of that month as a festival: they sought the Levites out of all their places, to bring them to Jerusalem, to keep the dedication with gladness; to assist in the solemnity of the day both with vocal and instrumental music, as follows: both with thanksgiving and with singing; with songs of praise and thankfulness vocally, that they had been able, notwithstanding all the malice of their enemies, to build the wall in so short a time; or with a song, perhaps the thirtieth psalm was sung on this occasion: with cymbals, psalteries, and with harps; some playing on one, and some on another, which were the three principal instruments of music used by them, see Ch1 15:16. (q) Megillath Thainith, c. 3. apud Selden. de Synedr. l. 3. c. 13. sect. 12.”