And Abijah stood up upon mount Zemaraim, which is in mount Ephraim, and said, Hear me, thou Jeroboam, and all Israel; Stood up upon Mount Zemaraim - "Which was a mount of the tribe of the house of Ephraim." - Targum. Jarchi thinks that Abijah went to the confines of the tribe of Ephraim to attack Jeroboam. It could not be Shomeron, the mount on which Samaria was built in the days of Omri king of Israel, 1 Kings 16:24.
Related Commentaries of 2 Chronicles 13:4
2 Chronicles 13:4
4 And Abijah stood up upon mount Zemaraim, which is in mount Ephraim, and said, Hear me, thou Jeroboam, and all Israel;