וְהַֽמְשַׁלֵּ֤חַ אֶת־הַשָּׂעִיר֙ לַֽעֲזָאזֵ֔ל יְכַבֵּ֣ס בְּגָדָ֔יו וְרָחַ֥ץ אֶת־בְּשָׂר֖וֹ בַּמָּ֑יִם וְאַחֲרֵי־כֵ֖ן יָב֥וֹא אֶל־הַֽמַּחֲנֶֽה׃
Ten zaś, który zawiódł kozła do Azazela, wypierze szaty swe i wykąpie ciało swoje w wodzie, poczém wejść może do obozu.
Mishnah Yoma
What did he do? He divided the thread of crimson wool, and tied one half to the rock, the other half between its horns, and pushed it from behind, and it went rolling down and before it had reached half its way down hill it had broken into limbs. He came back and sat down under the last booth until it grew dark. And from when are his clothes unclean? From the moment he has gone outside the walls of Jerusalem. Rabbi Shimon says: from the moment he pushes it into Zuk.