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.
Khitan (circumcision)
Most Shia traditions regard the practice as obligatory. They rely on sayings that come from classical Shia authors. In one narration Muhammad was asked if an uncircumcised man could go to pilgrimage. He answered "not as long as he is not circumcised". They quote Ali as saying: "If a man becomes Muslim, he must submit to circumcision even if he is 80 years old." Another narration from Al-Sadiq says: "Circumcise your sons when they are seven days old as it is cleaner (athar) and the flesh grows faster and because the earth hates the urine of the uncircumcised." It is also believed that the urine of the uncircumcised is impure, while if one prays with unclean genitals their prayer may not be considered as acceptable, even of those who have been circumcised, meaning that it may have to be repeated again at a time when the believer has purified themselves and removed the impurity. Another hadith of Muhammad states: "the earth cries out to God in anguish because of the urine of the uncircumcised", and that "the earth becomes defiled from the urine of the uncircumcised for forty days".