C. F. Keil and Franz Delitzsch on 2 Chronicles 35:25-27

2Ch 35:25-27

The death of the pious king was deeply lamented by his people. The prophet Jeremiah composed a lamentation for Josiah: “and all the singing-men and singing-women spake in their lamentations of Josiah unto this day;” i.e., in the lamentation which they were wont to sing on certain fixed days, they sung also the lamentation for Josiah. “And they made them (these lamentations) an ordinance (a standing custom) in Israel, and they are written in the lamentations,” i.e., in a collection of lamentations, in which, among others, that composed by Jeremiah on the death of Josiah was contained. This collection is, however, not to be identified with the Lamentations of Jeremiah over the destruction of Jerusalem and the kingdom of Judah, contained in our canon. - On 2Ch 35:26. cf. 2Ki 23:28. הסדיו as in 2Ch 32:32. בת כּכּתוּב, according to that which is written in the law of Moses, cf. 2Ch 31:3. וּדבריו is the continuation of דּברי יתר (2Ch 35:26).