וְהַכֹּהֵן֩ הַגָּד֨וֹל מֵאֶחָ֜יו אֲֽשֶׁר־יוּצַ֥ק עַל־רֹאשׁ֣וֹ ׀ שֶׁ֤מֶן הַמִּשְׁחָה֙ וּמִלֵּ֣א אֶת־יָד֔וֹ לִלְבֹּ֖שׁ אֶת־הַבְּגָדִ֑ים אֶת־רֹאשׁוֹ֙ לֹ֣א יִפְרָ֔ע וּבְגָדָ֖יו לֹ֥א יִפְרֹֽם׃
Y el sumo sacerdote entre sus hermanos, sobre cuya cabeza fué derramado el aceite de la unción, y que hinchió su mano para vestir las vestimentas, no descubrirá su cabeza, ni romperá sus vestidos:
Rashi on Leviticus
לא יפרע [THE HAIR OF HIS HEAD] SHALL HE NOT DISARRANGE — i.e. he shall not let his hair grow wild on account of ritual mourning for the death of a near relative (Sifra). And what is called "letting the hair grow wild”? Leaving it uncut for more than 30 days (Sanhedrin 22b).
Ramban on Leviticus
HE SHALL NOT LET THE HAIR OF HIS HEAD GO LOOSE etc. 11. NEITHER SHALL HE GO IN TO ANY DEAD BODY. The phrase [dealing with his hair, in Verse 10], is connected with any dead body in the following verse, thus stating that the High Priest is not to let his hair go loose nor rend his garments for any dead body, neither is he to enter a tent where there is a corpse.