Why was circumcision such a big deal in the early Gentile churches?
Circumcision became a major issue because Jewish legalists brought it into Gentile churches as a required work. Tying any fleshly act to salvation cancels the cross’s finished work, obligates a person to keep the whole law, and puts one under legalism rather than grace.
Les explains that circumcision was the big deal then because the Jewish people were bringing it in among the Gentile churches. But he points out this can be anything done in the energy of the flesh—joining the church, being baptized, taking the Lord’s Supper, or good works—as long as it is tied to salvation, it cancels the work of the cross. Paul testifies that a circumcised person becomes a debtor to do the whole law, which only Christ Himself could keep, making it an utter impossibility. Christ becomes of no effect to those justified by law, legalism, or flesh, and they fall from grace—not by losing salvation, but by turning their back on what God has provided.