Matthew Henry on 2 Chronicles 17:10–end
We have here a further account of Jehoshaphat's great prosperity and the flourishing state of his kingdom.
I. He had good interest in the neighbouring princes and nations. Though he was not perhaps so great a soldier as David (which might have made him their terror), nor so great a scholar as Solomon (which might have made him their oracle), yet the fear of the Lord fell so upon them (that is, God so influenced and governed their spirits) that they had all a reverence for him, Ch2 17:10. And, 1. None of them made war against him. God's good providence so ordered it that, while the princes and priests were instructing and reforming the country, none of his neighbours gave him any molestations…
Read the whole note in the consoleJamieson-Fausset-Brown on 2 Chronicles 17:11
Also some of the Philistines brought Jehoshaphat presents, and tribute silver--either they had been his tributaries, or they were desirous of securing his valuable friendship, and now made a voluntary offer of tribute. Perhaps they were the Philistines who had submitted to the yoke of David (Sa2 8:1; Psa 60:8).
the Arabians--the nomad tribes on the south of the Dead Sea, who, seeking the protection of Jehoshaphat after his conquest of Edom, paid their tribute in the way most suitable to their pastoral habits--the present of so many head of cattle.
Adam Clarke on 2 Chronicles 17:11
The Philistines brought - presents - They and the Arabians purchased peace with the king of Judah by paying an annual tribute. The Philistines brought silver, and no doubt different kinds of merchandise, The Arabs, whose riches consisted in cattle, brought him flocks in great abundance, principally rams and he-goats.
John Gill on 2 Chronicles 17:12
And Jehoshaphat waxed great exceedingly,.... In wealth and riches, power and authority, in his forces and fortifications:
and he built in Judah castles, and cities of stores; castles for the defence of his kingdom, and store cities to lay up corn, and wine, and all provisions, in case of an invasion, or against a time of war.