Uncovering, priah
At the neonatal stage, the inner preputial epithelium is still linked with the surface of the glans. The mitzvah is executed only when this epithelium is either removed, or permanently peeled back to uncover the glans. On medical circumcisions performed by surgeons, the epithelium is removed along with the foreskin, to prevent post operative penile adhesion and its complications. However, on ritual circumcisions performed by a mohel, the epithelium is most commonly peeled off only after the foreskin has been amputated. This procedure is called priah (Hebrew: פריעה), which means: 'uncovering'.
According to Rabbinic interpretation of traditional Jewish sources, the 'priah' has been performed as part of the Jewish circumcision since the Israelites first inhabited the Land of Israel. However, the Oxford Dictionary of the Jewish Religion, argues that many Hellenistic Jews had an operation performed to conceal the fact of their circumcision, and that similar action was taken during the Hadrianic persecution, in which period a prohibition against circumcision was issued. Thus, hypothesize the editors, it was probably in order to prevent the possibility of obliterating the traces of circumcision that the rabbis added to the requirement of cutting the foreskin that of priah. The frenulum may also be cut away at the same time, in a procedure called frenectomy. According to Shaye J. D. Cohen, in Why Aren't Jewish Women Circumcised?: Gender and Covenant in Judaism, pg 25, the Torah only commands circumcision (milah.) David Gollaher has written that the rabbis added the procedure of periah to discourage men from trying to restore their foreskins: ‘Once established, periah was deemed essential to circumcision; if the mohel failed to cut away enough tissue, the operation was deemed insufficient to comply with God's covenant’ and ‘Depending on the strictness of individual rabbis, boys (or men thought to have been inadequately cut) were subjected to additional operations.’
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