וַיֹּאמֶר֩ מֶ֨לֶךְ יִשְׂרָאֵ֜ל אֶל־יְהוֹשָׁפָ֗ט הִתְחַפֵּשׂ֙ וָבֹ֣א בַמִּלְחָמָ֔ה וְאַתָּ֖ה לְבַ֣שׁ בְּגָדֶ֑יךָ וַיִּתְחַפֵּשׂ֙ מֶ֣לֶךְ יִשְׂרָאֵ֔ל וַיָּב֖וֹא בַּמִּלְחָמָֽה׃
I rzekł król izraelski do Jozafata: Ja się przebiorę, a pójdę tak do boju; ty zaś zachowaj szaty swoje. Przebrał się tedy król izraelski i poszedł do boju.
Rashi
The king of Yisroel said to Yehoshofot, I will disguise myself and go into battle. To disguise himself and go [into battle]. I will disguise myself, [i.e.,] I will change my royal garments, so that they will not recognize me, for if they recognize me, they will turn toward me to attack.
Rashi
But you wear your own [royal] garments. That you are wearing, for you are not the king of Yisroel, but the king of Yehudah, and they have no conflict with you.