Charles Ellicott Commentary 1 Chronicles 2:7

"And the sons of Carmi: Achar, the troubler of Israel, who committed a trespass in the devoted thing." — 1 Chronicles 2:7 (ASV)

The sons of Carmi: See Note on 1 Chronicles 1:41.

Achar, the troubler of Israel: See Joshua 7:1, where the man is called Achan, son of Carmi, son of Zabdi, son of Zerah, of the tribe of Judah. The family of Carmi, therefore, were Zarhites. Joshua 7:24 calls him Achan, the son of Zerah, an expression which shows, if further proof were needed, that we must be cautious of interpreting such phrases literally in all instances.

Achar ... troubler of Israel: There is a play on the man’s name in the Hebrew, which is, “Achar ’ocher Yisrael.” So in Joshua 7:25 Joshua asks, Why have you troubled us? (‘achartânu’), and in 1 Chronicles 2:26 the place of Achar’s doom is called the valley of Achor (trouble). Probably Achan is an old error for Achar.