Circumcision

"For the Hebrews, circumcision and the relationship it established among man, his penis, and God was a divinely mandated sign of affiliation with the Almighty--and with themselves. It was required not of priests alone, but of every Israeite male on the eighth day of his life. The theological orgins are spelled out in Genesis, where God offers a covenant to Abraham (nee Abram), then ninety-nine years old, and his "seed." This covenant establishes the Almighty as sole diety of the Hebrews, who are promised a homeland in Canaan, where they will be "exceedingly fruitful," even Abraham, who is told that he, too, will once again become a father. the ancient desert dweller can only chortle at such a prospect. "Shall a child be born," he asks, "to a man who is a hundred years old?" This is no problem for God, of course, but in return he requires a sign: "Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskins, and it shall be a sign of the covenant between me and you." The Torah reports Abraham quickly cut off the foreskin from himself and every male that was born in his house, and all that were "bought with [his] money." (Left out is the reaction of those men and boys when this wizened goatherd emerged from his tent with a bloody stone in his hand and loudly declared what God had just commanded him to do.)"
- David Friedman in A Mind of Its Own pg 11