For we are the circumcision, who worship God in the spirit, and rejoice in Christ Jesus, and have no confidence in the flesh.
All Commentaries on Philippians 3:3 Go To Philippians 3
Ambrosiaster
AD 400
It is evident that those who are faithful are circumcised in their own hearts. By cutting away the cloud of error, they see and recognize the Lord of creation. This is what it means to “serve in the Spirit” and “glory in the Lord Jesus Christ.”