Circumcision
Circumcision is very important to most branches of Judaism, with over 90% of male adherents having the procedure performed as a religious obligation. The basis for its observance is found in the Torah of the Hebrew Bible, in Genesis chapter 17, in which a covenant of circumcision is made with Abraham and his descendants. Jewish circumcision is part of the "brit milah" ritual, to be performed by a specialist ritual circumciser, a "mohel", on the eighth day of a newborn son's life, with certain exceptions for poor health. Jewish law requires that the circumcision leaves the glans bare when the penis is flaccid. Converts to Conservative and Orthodox Judaism must also be circumcised; those who are already circumcised undergo a symbolic circumcision ritual. Circumcision is not required by Judaism for one to be considered Jewish, but some adherents foresee serious negative spiritual consequences if it is neglected.
Religious male circumcision
Authority derives from the age-group and the age-set. Prior to circumcision a natural leader or Olaiguenani is selected; he leads his age-group through a series of rituals until old age, sharing responsibility with a select few, of whom the ritual expert (Oloiboni) is the ultimate authority. Masai youths are not circumcised until they are mature, and a new age-set is initiated together at regular intervals of twelve to fifteen years. The young warriors (Il-Murran) remain initiates for some time, using blunt arrows to hunt small birds which are stuffed and tied to a frame to form a head-dress. Traditionally, among the Luhya, boys of certain age-sets, typically between 8 and 18 years of age would, under the leadership of specific men engage in various rites leading up to the day of circumcision. After circumcision, they would live apart from the rest of society for a certain number of days. Not even their mothers nor sisters would be allowed to see them.