A Kohen must not enter the Temple with long hair

This mitzvah forbids kohanim from performing service or entering the Mikdash with long, uncut, or unkempt hair. The requirement to maintain a neat and dignified appearance reflects the reverence and discipline expected in Hashem’s house.

Rambam explains that just as a person would not appear before a king disheveled, so too the kohanim must approach Hashem with dignity and order. The Sefer HaChinuch emphasizes that the prohibition prevents disrespect to the Temple and ensures the kohanim remain mindful of their sacred role.

The command parallels other requirements for priestly decorum, such as wearing the garments properly and refraining from intoxication. Together, these rules create a framework of external respect that fosters inner awe. Neglecting appearance suggests carelessness, which undermines the sanctity of the Divine service.

Commentary & Classical Explanation:

• Rambam (Hilchot Bi’at HaMikdash 1:7–8): Rules that long, unkempt hair invalidates a kohen’s service in the Mikdash.
• Sefer HaChinuch (Mitzvah 153): Teaches that proper grooming honors Hashem and prevents a casual attitude toward the Mikdash.
• Rashi (Lev. 10:6): Notes that the Torah prohibits kohanim from appearing disheveled in the Temple as a sign of reverence.
• Talmud (Sanhedrin 22b): States that kohanim must trim their hair regularly before serving, just as one would prepare to meet royalty.
• Ramban: Adds that these external requirements preserve awe in the eyes of the people, who looked to the kohanim as representatives of holiness.