וַיְהִ֧י יְהוֹשָׁפָ֛ט הֹלֵ֥ךְ וְגָדֵ֖ל עַד־לְמָ֑עְלָה וַיִּ֧בֶן בִּֽיהוּדָ֛ה בִּירָנִיּ֖וֹת וְעָרֵ֥י מִסְכְּנֽוֹת׃
And Jehoshaphat waxed great exceedingly; and he built in Judah castles and cities of store.
Read midrashic interpretation of II Chronicles 17:12: and classical rabbinic exegesis.