וַיְהִ֖י בַּשָּׁנָ֣ה הַשְּׁלִישִׁ֑ית וַיֵּ֛רֶד יְהוֹשָׁפָ֥ט מֶֽלֶךְ־יְהוּדָ֖ה אֶל־מֶ֥לֶךְ יִשְׂרָאֵֽל׃
אָבער עס איז געװען אױפֿן דריטן יאָר, האָט יהוֹשפֿט דער מלך פֿון יהוּדה אַראָפּגענידערט צו דעם מלך פֿון ישׂראל.
Rashi
And he went down at the end of years And in I Kings (22:2) it is written: “And it was in the third year, that Jehoshaphat came down, etc.” This refers to the third year since he had released Ben Hadad (ibid. 20:34).