With regard to circumcision, one of the reasons for it is, in my opinion, the wish to bring about a decrease in sexual intercourse and a weakening of the organ in question, so that this activity be diminished and the organ be in as quiet a state as possible. It has been thought that circumcision perfects what is defective congenitally... How can natural things be defective so that they need to be perfected from outside, all the more because
we know how useful the foreskin is for that member? In fact this commandment has not been prescribed with a view to perfecting what is defective congenitally, but to perfecting what is defective morally. The bodily pain caused to that member is the real purpose of circumcision.... The fact that circumcision weakens the faculty of sexual excitement and sometimes perhaps diminishes the pleasure is indubitable. For if at birth this member has been made to bleed and has had its covering taken away from it, it must indubitably be weakened.
-Maimonides,
Guide to the Perplexed
