1 Chronicles 2:7

And the sons of Carmi; Achar, the troubler of Israel, who transgressed in the thing accursed.

The genealogy names the son of Carmi as Achar, the troubler of Israel. The spelling Achar keeps alive the name tied to his wrongdoing and to the retribution that followed it. His transgression was stealing goods that were forbidden because they had been devoted to destruction.

That theft brought trouble upon Israel as a whole. The people were held responsible for its consequences and took part in inflicting his punishment.