The topic of circumcision, particularly its necessity for salvation and inclusion in the Christian faith, is addressed in several passages of the New Testament. The early church grappled with the question of whether Gentile converts to Christianity were required to undergo circumcision according to the Mosaic Law. This issue is most prominently discussed in the context of the Jerusalem Council and the writings of the Apostle Paul.

Jerusalem Council (Acts 15):
The Jerusalem Council, as recorded in Acts 15, was convened to address the controversy surrounding the necessity of circumcision for Gentile believers. Certain individuals from Judea were teaching, "Unless you are circumcised according to the custom of Moses, you cannot be saved" (Acts 15:1). This teaching caused significant debate and division among the early Christians. The apostles and elders gathered to consider this matter, and after much discussion, Peter stood up and reminded them that God had already given the Holy Spirit to the Gentiles, just as He had to the Jews, without the requirement of circumcision (Acts 15:7-11). The council ultimately concluded that circumcision was not necessary for salvation, emphasizing that salvation is through the grace of the Lord Jesus (Acts 15:11).

Paul's Epistles:
The Apostle Paul addresses the issue of circumcision in several of his letters, particularly in Galatians and Philippians. In Galatians, Paul expresses strong opposition to the teaching that circumcision is necessary for salvation. He writes, "Mark my words! I, Paul, tell you that if you let yourselves be circumcised, Christ will be of no value to you at all" (Galatians 5:2). Paul argues that justification comes through faith in Jesus Christ, not by observing the law (Galatians 2:16). He warns the Galatians that accepting circumcision obligates them to obey the entire law, which is contrary to the freedom found in Christ (Galatians 5:3-4).

In Philippians, Paul cautions believers to "watch out for those dogs, those workers of evil, those mutilators of the flesh" (Philippians 3:2). Here, Paul uses strong language to describe those who insist on circumcision as a requirement for Christians. He contrasts this with the true circumcision, which is spiritual and characterized by worshiping in the Spirit of God and glorying in Christ Jesus (Philippians 3:3).

Theological Implications:
The New Testament teaching on circumcision underscores the transition from the Old Covenant, based on the law, to the New Covenant, centered on faith in Christ. Circumcision, once a sign of the covenant between God and Abraham's descendants, is no longer a requirement for God's people under the New Covenant. The emphasis is on a circumcision of the heart, a spiritual transformation brought about by faith in Jesus Christ (Romans 2:28-29).

The warning against circumcision as a requirement for salvation serves as a broader caution against legalism and the belief that adherence to the law can achieve righteousness. The New Testament consistently teaches that salvation is a gift of grace, received through faith, and not by works of the law (Ephesians 2:8-9). This teaching affirms the sufficiency of Christ's sacrifice and the believer's freedom in Him.