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.
Brit milah
Many European Jewish fathers during the nineteenth century chose not to circumcise their sons, including Theodor Herzl. However, unlike many other forms of religious observance, it remained one of the last rituals Jewish communities could enforce. In most of Europe, both the government and the unlearned Jewish masses believed circumcision to be a rite akin to baptism, and the law allowed communities not to register uncircumcised children as Jewish. This legal maneuver spurred several debates addressing the advisibility of its use, since many parents later chose to convert to Christianity. In early 20th-century Russia, Chaim Soloveitchik advised his colleagues to reject this measure, stating that uncircumcised Jewish males are no less Jewish than Jews who violate other commandments.