What does Philippians 3:5 mean?

Verses 5 and 6 provide a list of seven important traits found in Paul's life as a devout Jew. His reason for listing these is to prove that he, of all people, has the right to comment on the futility of works. Paul is not claiming salvation by faith as an escape attempt. His message is not an excuse for personal failure—that he cannot, or will not, meet some requirement of the Old Testament law. On the contrary, Paul has fulfilled it better than those who criticize him for preaching saving faith!

Paul's birth and ancestry were impeccable, according to Jewish standards. Paul had been circumcised on the eighth day. His parents did this in accordance with God's command given to Abraham (Genesis 17:12). Paul was truly, naturally, of the "people of Israel." In other words, he was born Jewish rather than being a convert to Judaism. Specifically, he was from the tribe of Benjamin.

Paul's training and lifestyle were also perfect, according to Judaism. Paul calls himself a "Hebrew of Hebrews." He was raised according to Jewish customs and had learned the Hebrew language (Acts 22:2). Paul was a Pharisee, the most religiously conservative group of Jews in his time. Pharisees were known for strictly following Jewish laws and customs. They are particularly noted in the Gospels for their devotion to traditions of the law. They felt that this kept them pure before the Lord. Interestingly, this verse is the only mention of Pharisees outside of the Gospels and Acts.