וּפָשַׁט֙ אֶת־בְּגָדָ֔יו וְלָבַ֖שׁ בְּגָדִ֣ים אֲחֵרִ֑ים וְהוֹצִ֤יא אֶת־הַדֶּ֙שֶׁן֙ אֶל־מִח֣וּץ לַֽמַּחֲנֶ֔ה אֶל־מָק֖וֹם טָהֽוֹר׃
And he shall put off his garments, and put on other garments, and carry forth the ashes without the camp unto a clean place.
Read kabbalistic (mystical) interpretation of Leviticus 6:4: and classical mystical sources.