Leviticus 21:10

And the priest that is chief among his brethren, the oil having been poured upon the head of the anointed one, and he having been consecrated to put on the garments, shall not take the mitre off his head, and shall not rend his garments:

And he that is the high priest among his brethren, upon whose head the anointing oil was poured, and that is consecrated to put on the garments, shall not uncover his head, nor rend his clothes;

“‘He who is the high priest among his brothers, upon whose head the anointing oil is poured, and who is consecrated to put on the garments, shall not let the hair of his head hang loose, or tear his clothes.