Philippians 3:1-2: Rejoice in the Lord

Paul again exhorts the church to rejoice in the Lord in the midst of their trials. Pastor Josh explains why it is Christians above all people who can rejoice and remain steadfast in the evils of the day, including government corruption. Paul also warns the church of false teachers, whom he calls dogs, evil workers, and mutilaters of the flesh. Why does Paul use such harsh language against these teachers, and is there a place for such language in the Christian life?