Albert Barnes Commentary 2 Chronicles 17:11

"And some of the Philistines brought Jehoshaphat presents, and silver for tribute; the Arabians also brought him flocks, seven thousand and seven hundred rams, and seven thousand and seven hundred he-goats." — 2 Chronicles 17:11 (ASV)

Some of the Philistines brought Jehoshaphat presents - That is, “some of the Philistines were among his tributaries.” Compare 2 Samuel 8:2; 1 Kings 4:21.

Tribute silver - Or, “much silver”—literally “silver of burden.”

The Arabians - The Arab tribes who bordered Judea to the south and the southeast paid Jehoshaphat a fixed tribute in kind. Compare 2 Kings 3:4 note.