In Philippi, however, certain teachers had come in trying to establish their own righteousness. They insisted on what Paul called “the mutilation of the flesh.” By doing this, they were missing the whole point of circumcision by putting their confidence in the flesh and not in Jesus. This is absolutely contradictory to the gospel of God’s free grace. When we get the gospel wrong, tragically, we inevitably get worship wrong. That is, because we will replace Jesus with something or someone else, all praise, honor, and glory cannot go to Him. That was the fatal misstep of these false teachers. Circumcision was intended to point beyond the physical sign, but they were too nearsighted to see the spiritual truth and gloried in a Christ-substitute. Paul spared no words as he put down this evil and vain confidence in the flesh.
The true circumcision—not those circumcised in the flesh—are those who worship by the Spirit of God and glory in Jesus Christ. Paul insists on that because true worship is not just skin deep. Worship is a response that comes when the Spirit gives our hearts an apprehension of the righteousness of Jesus provided in the gospel as we praise His glorious grace. This, according to the Apostle, characterizes a life of discipleship. To be a disciple of Jesus is to forgo all confidence in anything but Jesus and to glory in His person and work with the melody of heart and tongue.