1 “Finally, my brothers and sisters, rejoice in the Lord. To write the same things again is no trouble for me, and it is a safeguard for you.2 Beware of the dogs, beware of the evil workers, beware of the false circumcision; 3 for we are the true circumcision, who worship in the Spirit of God and take pride in Christ Jesus, and put no confidence in the flesh,4 although I myself could boast as having confidence even in the flesh. If anyone else thinks he is confident in the flesh, I have more reason:5 circumcised the eighth day, of the nation of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; as to the Law, a Pharisee; 6 as to zeal, a persecutor of the church; as to the righteousness which is in the Law, found blameless.”
Beware: Paul is warning the church in Philippi of the same heresies present in Galatians, Ephesus, and Colossae. There existed an odd mixture of Judaism with the Gospel in these churches. The believers in Philippi, who were Gentiles, needed to be warned of these false teachings. Gentiles never had the law and yet these heretics were trying to urge them to follow a pseudo-Christianity which mixes law and Gospel in order to somehow be closer to God. Any mixture of law and Gospel is an insult to Christ.
No confidence in the flesh: Paul could give his impressive religious resume as a Pharisee. He could even list the miraculous signs he demonstrated as a Christians to somehow prove his worthiness as an apostle. And yet none of these outward works ultimately mattered to Paul when compared to the greatness of knowing Christ Jesus. Paul’s confidence for identity and worth was in Christ and Christ alone. The false teachings, however, placed confidence in the flesh because they emphasized performance before God. So, for Paul, the Gospel was the only path to righteousness. In Christ, and only in Christ, are we the righteousness of God (see 2 Corinthians 5:21).