וְלִבְנֵ֤י אַהֲרֹן֙ תַּעֲשֶׂ֣ה כֻתֳּנֹ֔ת וְעָשִׂ֥יתָ לָהֶ֖ם אַבְנֵטִ֑ים וּמִגְבָּעוֹת֙ תַּעֲשֶׂ֣ה לָהֶ֔ם לְכָב֖וֹד וּלְתִפְאָֽרֶת׃
And for Aaron’s sons thou shalt make tunics, and thou shalt make for them girdles, and head-tires shalt thou make for them, for splendour and for beauty.
Read kabbalistic (mystical) interpretation of Exodus 28:40: and classical mystical sources.