“You shall fashion the holy garments for your brother Aharon for kovod (honor) and tiferes (beauty)” (28:2). The Ohr HaChaim asks why HaShem commanded Moshe to make eight garments: four white and four gold. The answer the pasuk gives us is that these garments were made for kovod and tiferes – honor and beauty.
The Ohr HaChaim explains based on the Zohar (Tikkunim) that the eight garments allude to the two divine Names of HaShem each spelled with four letters, YHV”H and ADN”Y. The four white garments hint at the four letters of YHV”H and the four gold garments at ADN”Y. The name of HaShem (YHV”H) is associated with tiferes and the name ADN”Y is associated with kovod. This is why the pasuk tells us that Moshe is told to fashion the garments for kovod and tiferes; kovod refers to the golden garments and tiferes to the white ones.
