Charles Ellicott Commentary 2 Samuel 10:18

"And the Syrians fled before Israel; and David slew of the Syrians [the men of] seven hundred chariots, and forty thousand horsemen, and smote Shobach the captain of their host, so that he died there." — 2 Samuel 10:18 (ASV)

Seven hundred chariots. —In this campaign David delivered a crushing blow upon his foes, from which they did not recover during the rest of his reign or that of his son. For the seven hundred here, 1 Chronicles 19:18 has seven thousand, which is almost an incredible number of chariots, and the number here is evidently the more correct; but the same place has forty thousand footmen, while here it is forty thousand horsemen. Probably both statements are meant to include both infantry and cavalry, though only one of them is specifically mentioned in each case. Compare to the note on 2 Samuel 10:6.