Peyos - Sidelocks
What is the meaning of the long curls worn by religious Jewish men?
The Aish Rabbi Replies:
The Torah says, "You shall not round off the peyos of your head" (Leviticus 19:27). The word peyos refers to sideburns. The exact definition of sideburns refers to the hair in front of the ears that extends to underneath the cheekbone which is level with the nose (Talmud – Makkot 20a). The Talmud explains that this law only applies to men, not to women.
Maimonides explains that the prohibition of "rounding" prohibits the complete removal of the sideburns, by any means. However, it is permitted to trim the sideburns, even very close to the skin, using scissors.
Even though sideburns are enough to satisfy the Torah requirement of peyos, many Jews grow their peyos long as a way of emphasizing the commandment (peyos sounds like pious, right?!), or simply of Jewish identification. Some will curl their peyos, while others while tuck them behind their ear. It's just a matter of individual taste, or communal custom.
Hair is also a symbol of vanity, a preoccupation of how one looks. The prohibition against cutting off the peyos reminds a person that he shouldn't overrate his looks when wishing to express himself, rather he should depend on intellect and good character. (Rabbi Samson Raphael Hirsch, 19th century Germany)
From a mystical perspective, peyos separate between the front part of the brain which is used for abstract thought (i.e. spirituality), and the back part of the brain that governs the body.