Philip. 3:2-11 (ESV)
Look out for the dogs, look out for the evildoers, look out for those who mutilate the flesh.  For we are the real circumcision, who worship by the Spirit of God and glory in Christ Jesus and put no confidence in the flesh—  though I myself have reason for confidence in the flesh also. If anyone else thinks he has reason for confidence in the flesh, I have more:  circumcised on the eighth day, of the people of Israel, of the tribe of Benjamin, a Hebrew of Hebrews; as to the law, a Pharisee;  as to zeal, a persecutor of the church; as to righteousness, under the law blameless.  But whatever gain I had, I counted as loss for the sake of Christ.  Indeed, I count everything as loss because of the surpassing worth of knowing Christ Jesus my Lord. For his sake I have suffered the loss of all things and count them as rubbish, in order that I may gain Christ  and be found in him, not having a righteousness of my own that comes from the law, but that which comes through faith in Christ, the righteousness from God that depends on faith—  that I may know him and the power of his resurrection, and may share his sufferings, becoming like him in his death,  that by any means possible I may attain the resurrection from the dead.
Actually this is quite a scandalous section of scripture. Dogs was the colloquial equivalent of faggot in Paul’s day and here they are equated with those who would put you back under the law, and tell you there is still something you need to do to be saved. The word translated rubbish in verse 8 is better translated dung, but was most often used in a manner the equivalent of the English “shit.” Paul was not politically correct, neither is Christianity. Paul had a point to make and he would make it as forcefully as possible. I hate the sanitation of the English translation, “like kissing a girl through cellophane,” I heard one prof. say. Like practicing safe sex with your wife might be more appropriate. Never heard of kissing a girl through cellophane.
In any case Paul tackles it head on. There is no confidence in the flesh, point to what you will without Christ it is shit. It definitely is If you are pulling these things out to build up your own ego, and obscure the cross. It is comical at times. Absolutely comical. People tearing phone books in the name of Christ. Bearing their testimony, that does nothing but give me good ideas of how to out do you in the sin department. You slept with six girls, so the next guy gets up and says 12. You gave up smoking, the next guy gave up heroine. Who cares? That isn’t Christianity. Christianity is the fact Christ forgave you for taking time out of my precious day to tell me how good you are now, in the same breath with which you brag about your past sins. I got news, you’re still evil, and Jesus still forgives you