The central issue Paul is addressing throughout the book is the demand that false teachers are placing on Gentiles who have accepted Jesus Christ to be circumcised in order to become complete Christians. In fact, the act of physical circumcision represented the entering into a life of Judaism, which carried with it a number of physical, outward manifestations as prescribed in the law and through the traditions of the Judaic fathers (e.g., various washings, wearing tassels, hair and beard grooming, etc.).
Paul shows how it is not physical circumcision that makes one a convert, a new creation, but inward circumcision of the heart. Paul warns us to beware of those who demand physical, religious practices of the outer man. He makes clear that physical signs of religion, such as circumcision, do not perfect you, but rather growth in faith, belief and love as believers in Christ, who walk according to the Spirit and not the flesh.
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