Matthew Poole and continuators on 2 Chronicles 20:25

25 And when Jehoshaphat and his people came to take away the spoil of them, they found among them in abundance both riches with the dead bodies, and precious jewels (which they stript off for themselves) more than they could carry away: and they were three days in gathering of the spoil, it was so much.

Which they brought with them partly to corrupt any of Jehoshaphats Officers as they saw Occasion: partly to procure necessaries for their vast Army from time to time: and partly because they came as to a Triumph rather than to a Fight, being secure and confident of the Victory because of their great Numbers, and especially because they thought to surprize Jehoshaphat ere he could make any considerable preparations against them; God also permitting them to be puffed up to their own Destruction.