Charles Ellicott Commentary 2 Chronicles 13:17

"And Abijah and his people slew them with a great slaughter: so there fell down slain of Israel five hundred thousand chosen men." — 2 Chronicles 13:17 (ASV)

Slew them with a great slaughter. —Literally, He struck a great blow among them.Numbers 11:33.

Five hundred thousand chosen men. —Or more than half of Jeroboam’s entire army.

It is hardly true to say that “there is nothing in the original to indicate that this slaughter was all on one day” (Speaker’s Commentary). On the contrary, it is perfectly evident from the whole narrative that this verse describes the outcome of a single great and decisive encounter of the rival hosts.

The result is certainly incredible if the numbers are pressed; but it seems more reasonable to see in them “only a numerical expression of the belief of contemporaries of the war, that both kings had made a levy of all the fighting men in their respective realms, and that Jeroboam was defeated with such slaughter that he lost more than half his warriors” (Keil). The Syriac reads “five thousand.”

The number of slain on the other side is not stated. But it is absurd to talk as Reuss does, of Abijah’s 400,000 as being “still intact,” and then to ask why they did not proceed to subdue the northern kingdom.