Charles Ellicott Commentary 2 Chronicles 25:11

"And Amaziah took courage, and led forth his people, and went to the Valley of Salt, and smote of the children of Seir ten thousand." — 2 Chronicles 25:11 (ASV)

And Amaziah strengthened himself. — He showed himself strong or courageous, took courage; as the prophet had instructed him to do (2 Chronicles 25:8). (Compare to 2 Chronicles 15:8.)

And went to the valley of salt. — Compare to 2 Kings 14:7: He it was who smote Edom in the valley of salt ten thousand; and he took Sela in the war, and called its name Joktheel, unto this day. The valley of salt lay to the south-east of the Dead Sea (2 Samuel 8:13; 1 Chronicles 18:12).