In the beginning of Parshat Tazria we are told about the Mitzva of Brit Mila (circumcision). Many Meforshim struggle to understand this Mitzva. The Rambam writes in his Guide to the Perplexed that whenever a cut is made on the human body, that area becomes weaker than it was in its original state. Therefore, we perform a Brit Mila in order to lessen the drive of a man.
The Abarbanel says that the Brit Mila is an atonement for the sin of Adam and Chava. However, the Or HaChaim asks the Abarbanel why a woman does not have some sort of Brit Mila equivalent. After all, Chava not only ate from the Eitz Hadaat, but also convinced Adam to eat from the tree. The Abarbanel answers that a woman's natural cycles remind her of the role Chava played in the sin.
The Kli Yakar believes that the Brit Mila is symbolic of the removal of the barrier that separates man's heart from Hashem. According to the Ramban, this notion is a common misconception. Rather, the Brit is a covenant to remind Hashem to show special consideration to a Jew, especially when he sins. He cites the idea that Brit Mila is similar to a Korban - both atone for sins. The Rambam further notes that a Korban must be at least eight days old, just like a newborn baby. However, the Brit Mila is to be considered the higher sacrifice since it is performed directly upon the body of a human being, and not on an animal surrogate.
The Chinuch suggests that the Mitzvah of Brit Mila has a powerful dual message for Am Yisrael. First, it separates us from the non-Jews even in our physical bodies. Second, the distinction between us and our non-Jewish neighbors is expressed in the part of our body responsible for reproduction, emphasizing that this distinction must be passed on to our descendants.
The Chinuch continues to relate how the Brit Mila is a step towards perfection, based on the question of why males are born with this additional foreskin. His conclusion is that Hashem purposely did not create us perfectly. Our imperfection teaches us that even in our everyday lives, we must strive for perfection in our minds and in our hearts.