וַיַּפְשֵׁט֩ מֹשֶׁ֨ה אֶֽת־אַהֲרֹ֜ן אֶת־בְּגָדָ֗יו וַיַּלְבֵּ֤שׁ אֹתָם֙ אֶת־אֶלְעָזָ֣ר בְּנ֔וֹ וַיָּ֧מָת אַהֲרֹ֛ן שָׁ֖ם בְּרֹ֣אשׁ הָהָ֑ר וַיֵּ֧רֶד מֹשֶׁ֛ה וְאֶלְעָזָ֖ר מִן־הָהָֽר׃
And Moses stripped Aaron of his garments, and put them upon Eleazar his son; and Aaron died there in the top of the mount; and Moses and Eleazar came down from the mount.
Read kabbalistic (mystical) interpretation of Numbers 20:28: and classical mystical sources.