What is the reason for growing one's beard? Many rabbis have beards. Why?
- Kabbalistic sources about beards, or about spiritually-destructive forces involved in removing a beard. Much ink has been spilled over how much facial hair was worn by the kabbalist Rabbi Menachem Azariah of Fano.
- Cutting your beard means you're trying to look like a non-Jew. Chasam Sofer vehemently opposes this argument, observing that in Biblical times, pagan men had beards too.
- The Tzemach Tzedek (the 3rd Lubavitcher Rebbe) was of the opinion that you're trying to look feminine by removing your beard, which violates the prohibition on cross-dressing.
- Men are prohibited from shaving their jaw line ("five corners of the face", more or less) with a razor. So until a few decades ago, your only options were a scissors (which could trim your beard but not really eliminate it altogether) or depilatory powder (a strong base that would dissolve the hair). Today, most Americans follow the opinion of Rabbi Moshe Feinstein (and others) that most electric shavers are considered "scissors", not razors as they can't cut at 0 rpm; but some (such as Chazon Ish) disagree.
- There are various times in the year when shaving, haircuts, and other grooming are frowned-upon for men. (E.g. the three weeks commemorating the destruction of the Temple in Jerusalem.) Thus growing a beard all the time was just easier.
- Why waste the time shaving?
R Shlomo Aviner, in Shut She'elat Shlomo, mentions 4 reasons, which are brought here in short:
- The gmara in Shabbat 152a, says that the splendor of man's face is the beard
הדרת פנים זקן. That's the natural and whole looks of the Israeli man, as R Yehonatan Aibeshitz mentions in Ya'art Dvash, part A.
- The daily shaving is bothersome and causes bitul torah (not learning torah at that time).
- Whoever shaves daily, on Shabbat he cannot. So on Shabbat he's Menuval - not tidy. Same happens on holidays and Shabbats of Ben HaMetzarim and during Sfirat HaOmer.
- Even today, with the electric shavers, it isn't trivial that it's allowed to shave using them. Many Rabbis have ruled against it. Even those that approved it, stated that the machine oughtn't be pressed strongly to the skin and the skin oughtn't be stretched. New machines with new techniques for making the shave closer to the skin make their Halachich approval even harder.
the Meam Loez on Bereishis says the lion was given a beard to give it a majestic appearance (since it is king of the animals).
Hence, a beard is supposed to give a majestic appearance. So too regarding man. Judaism views man as a the crowning glory and ultimate purpose of creation.
Perhaps not shaving the beard is to remind a person of his great importance and mission in this world.
The book "Haderet Panim" a 400 plus page book about the beard which deals mainly with the halachic sources, citing Gemarrah, Minhag, Ktuvim and some sources in Zohar quote the Ari Z"L as saying that : "The hairs of the head are tzinaros of tumah while the hair of the beard are tzinaros of Kedusha.Tzinaros being "vessles". Modern biology 400 years later showed also that human hair is hollow like a drinking straw.