If you’re a man, you’re supposed not to shave it from your face (i.e., grow a beard and a mustache). You’re also supposed to grow your “Payot”, which is the Hebrew term for sidelocks or sideburns.
In fact, the 252nd of the 613 “Mitzvot” (613 commandments) of Judaism is: “…neither shalt thou mar the corners of thy beard” (Leviticus, chapter 19, verse 27). Certain Jewish religious sectors have managed to interpret this as a divine command to shave only using an electrical shaving machine. The Jewish religion also associates not shaving your beard with certain dates of the Jewish calendar, or while you’re officially mourning the death of a close relative.
Occasionally, hair-related verdicts become awkward. For example: When you pick your nose, there is an obvious danger you’ll tear out some hair, therefore the act is of picking your nose is forbidden on Saturdays, as cutting hair is officially considered “work”.
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If you’re a woman, the religious minds have found some different restrictions that have to do with hair. For example: In certain Jewish religious sectors you should simply cover it after you get married. Rabbi Ronen Shaulov was recently quoted explaining that children die in hospitals because of women not covering their hair.
In other ultra-Orthodox sectors, you should shave your hair altogether after you get married. So how do you avoid looking weird in 21st century public? You wear a wig of course, which is sort of self-defying the original purpose anyway. Hence the wig thing has recently also become a huge debate.
And that’s just the hair, and only a small part of the content.