Ezekiel 44:16-20

“They shall enter My sanctuary; they shall come near to My table to serve Me and assume the responsibility I give them.

And it shall be that when they enter at the gates of the inner courtyard, they shall be clothed with linen garments; and wool shall not be worn by them while they are ministering in the gates of the inner courtyard or in the house.

Linen turbans shall be on their heads and linen undergarments shall be around their waists; they shall not put on anything that makes them sweat.

And when they go out into the outer courtyard, into the outer courtyard to the people, they shall take off their garments in which they have been ministering and lay them in the holy chambers; then they shall put on other garments, so that they will not transfer holiness to the people with their garments.

Also they shall not shave their heads, yet they shall not let their locks grow long; they shall only trim the hair of their heads.