John Trapp on Isaiah 30:29

Verſe 29. Ye ſhall have a ſong] As, after the Paſſover eaten, they ſang an hymn; ſo after the Aſſyrian deſtroyed, there ſhall be a different ſound heard in their ſeveral camps. Apud utroſque audietur ſonus, & ſtrepitus, ſed diverſâ admodum ratione: ſo was fulfilled that of our Prophet, chap. 65.13, 14.

As in the night when an holy ſolemnity is kept] Pintus ſaith, that the night before ſome ſolemn ſacrifice, the Jews uſually ſpent in jollity and ſinging. They ſtill conclude their Sabbath with ſinging or caterwawling rather, which they continue as long as they can, for eaſe of the defunct fouls.