Leviticus 10:6

10:6 Then Moses said to Aaron and to Eleazar and Ithamar his other two sons, “Do not dishevel the hair of your heads and do not tear your garments, so that you do not die and so that wrath does not come on the whole congregation. Your brothers, all the house of Israel, are to mourn the burning which the Lord has caused,

Leviticus 21:10

Rules for the High Priest

21:10 “‘The high priest – who is greater than his brothers, on whose head the anointing oil is poured, who has been ordained to wear the priestly garments – must neither dishevel the hair of his head nor tear his garments.