Bris Milah (circumcision) is a covenant between God and the Jewish people, representing our commitment to use our creative powers to reveal the light of creation that is hidden within Torah. We do this primarily through speech, which is why the Bris is termed specifically "Bris Milah," the "Covenant of the Word."
Adam HaRishon was created circumcised, as it says, "God created man in His image ..." (Bereishis 2:5). Avos d'Rav Nossan 2:5
Rav Yitzchak said, [Adam] caused his foreskin to be extended [and cover his circumcision]. Sanhedrin 38b
Of the many consequences that resulted from the tragic mistake of the first man, death and suffering are two ills that we still contend with to this very day, and very few people accept either willingly. The growth of the foreskin, however, is one consequence that seems to be the least drastic. On the eighth day from the birth of a Jewish male child, parents and family happily anticipate the ritual of entering their child into the covenant of Avraham through the performance of Bris Milah. Although the actual "operation" does not seem the most natural of occurrences, Bris Milah is an accepted part of being Jewish.
Nevertheless, the profundity of the connection between the growth of the Orlah (foreskin) and the mistake of Adam is crucial to understand. For, whether we are talking about "Orlas HaLeiv" (uncircumcised heart), "Orel S'fasaim "(uncircumcised lips), or "Orlah" from a tree (fruits of the third year), the word Orlah always implies a spiritual "barrier" between man and God which has to be removed.
Logically, the connection should surface by understanding the mitzvah of Milah, given to Avraham at the age of ninety-nine years. For, it was Milah that elevated Avraham to an ultimate level of relationship with His Creator, removing any last spiritual barrier that may have stood between him and God:
When Avram was ninety-nine years old, God appeared to Avram and said to him, 'I am Kel-Shakai- walk before Me and be perfect.' Bereishis 17:1
The actual command to circumcise himself comes in the Torah after Avraham fought a successful campaign against the kings of Canaan (to free his nephew Lot who had been taken captive). It was then that God approached Avraham and said:
You shall circumcise the flesh of your foreskin, as a sign of the covenant between Me and you. At the age of eight days, you shall circumcise every male child born to you throughout the generations ... Bereishis 17:11-1
There are two aspects of the mitzvah referred to in the verse. Firstly, Milah is a sign of the covenant between Avraham and God; secondly, Milah is to take place on the eighth day from birth. We should take note of the point in the Parsha at which the Mitzvah is commanded after Avraham's successful routing of the Canaanite kings and after, what seems to be, an unusual reaction by Avraham.
Once Avraham had successfully subdued the enemy nations, and had restored the previously defeated kings, they gathered to pick up the pieces and to pay homage to Avraham. The king of S'dom offered Avraham:
"Give me the people, and the possessions take for yourself." Bereishis 14:21
At face value, the offer of the king of S'dom seems like a nice gesture. However, from Avraham's reaction (or rather, over-reaction) to it, we understand that the king of S'dom was trying to trick Avraham:
'I have vowed to God, the Most High, the Owner of heaven and earth! I will not take even a thread to a shoelace from anything of yours. You will not be able to say, 'I made Avraham rich.'
Was Avraham being melodramatic? Would not a polite refusal have accomplished the same purpose, without making a scene? Furthermore, if Avraham was so worried about taking money from anyone but God, why did he not put up the same resistance when Pharaoh loaded him down with riches? In Egypt, Avraham seemed completely unbothered when Pharaoh showered him with gifts to send him off back to Canaan.
The difference between the two gifts was not in the giving itself, but the circumstances that led to the giving. In each case, it was a miracle that led to Avraham finding favor in the eyes of his benefactor. However, the nature of the miracle was different. In Egypt, God had performed an obvious miracle when he sent the plague to Pharaoh and his entire household. The victory over the Canaanite kings, on the other hand, was a less obvious miracle, since Avraham had to fight the war.
For Pharaoh, there was no way to view Avraham's "victory" as being anything other than a miracle of God. Avraham did not go to war against him; on the contrary, Avraham waited passively while God inflicted Pharaoh and his court with sickness. Therefore, any reason Pharaoh might have to give to Avraham could only be viewed as the will of God. Pharaoh saw his giving as an obvious fulfillment of God's promise to make Avraham a wealthy man. As such, it was also a tremendous sanctification of God's name.
However, the king of S'dom could view Avraham's success in terms of natural forces, since he did fight. Therefore, any booty Avraham might take would not necessarily appear as a fulfillment of God's promise, and therefore, it could lack the potential to sanctify God's name. This, Avraham could not accept. By emphatically refusing the offer, and by stating why, Avraham sanctified God's name. He also, perhaps unbeknown to him at the time, rose to a whole new spiritual level, for which Bris Milah would be the reward.
When Adam ate from the tree, he plunged mankind into the world of nature. By depending upon the physical world to develop himself and his relationship to God, he in fact created a barrier between himself and God. He hardened his heart (Orlas HaLeiv), he reduced his Godly power of speech (Orel S'fasaim), he made the tree a barrier (Orlah), and abused his creative potential (symbolized by the Orlah removed by Bris Milah).
When Avraham melodramatically expressed his complete dependence on God for his physical sustenance, he demonstrated his unwavering commitment to live above nature. As a consequence, he was provided with the means to remove all the Orlos Adam's mistake had brought to mankind. This is the Bris Milah which is performed on the eighth day (eight always symbolizes the spiritual, supernatural realm, as we see through Chanukah as well).
Removing the Orlos, specifically the Orlah of Bris Milah, was an important corrective measure after eating from the forbidden tree. Furthermore, Bris Milah represents a commitment to live a moral life.