Charles Ellicott Commentary 2 Chronicles 34:21

"Go ye, inquire of Jehovah for me, and for them that are left in Israel and in Judah, concerning the words of the book that is found; for great is the wrath of Jehovah that is poured out upon us, because our fathers have not kept the word of Jehovah, to do according unto all that is written in this book." — 2 Chronicles 34:21 (ASV)

Go, inquire of the Lord. —The verse is virtually identical with 2 Kings 22:13.

For them that are left ... Judah. —This is an alteration of and for the people and for all Judah (from the Book of Kings). The chronicler thinks of the remnant in the northern kingdom.

Poured out. —The Book of Kings has kindled against. (So the Septuagint) This was probably the original reading, as the wrath which Josiah dreaded had not yet been poured out upon Judah. But the chronicler remembered the ruin of the ten tribes.

Kept. —The Book of Kings has hearkened to (shamĕ’û, as in this passage, instead of shâmĕrû; ), and so the Septuagint and Syriac.