Im currently reading the Bible for multiple reasons and as I go through Genesis circumcision is shown to be highly important. In the story "The defiling of Dinah" an entire town is destroyed because someone with an uncircumcised penis had sex with a follower of God. I was just wondering if there is broader historical context here, or even an answer wrapped in theology.
Just to clarify the Dinah story: The reason the town was destroyed was because Dinah was raped by one of the citizens of the city (and, according to some commentators, the failure of the city to punish the rape justified its destruction). The circumcision part was merely a ruse to make sure that the citizens couldn't fight back.
In the Hebrew Bible circumcision is the "sign of the covenant" between Israel and God. Various rituals (such as the Passover sacrifice) can be participated in only by the circumcised, and failure to carry the rite meant you were not truly one of the tribe.
Circumcision was an ancient practice among many peoples (it was seen in Sub-Saharan Africa, Egypt, and among the people that became the Israelites and then the Jews. It's not surprising that it acquired a religious significance when Judaism was codified.
A slight follow up question - wasn't the importance of circumcision more important to the Jews (Old Testament / Torah) than the Christians (New Testament)? Is there any knowledge on when, how, and why the importance of these older traditions faded with the advent of Christiantiy?