No one could declare my position more accurately and scripturally than Ernest Reisinger did here:
http://www.peacemakers.net/unity/carnal.htm
I think possibly Paul was challenging the validity of their salvation. Much still to analyze on this!
Reisinger includes this comment:
The 'carnal Christian' teaching is also the mother of one of the most soul-destroying teachings of our day. It suggests that you can take Jesus as your Savior and yet treat obedience to his lordship as optional. How often is the appeal made to the so-called 'carnal Christians' to put Jesus on the throne and 'make him Lord'! When they accept Jesus as Lord, they are told, they will cease to be 'carnal Christians'. But such teaching is foreign to the New Testament. When our Lord appeared in human form in history the angel announced his coming in the words, 'For unto you is born this day in the city of David a Savior, which is Christ the Lord' (Luke 2:11). He cannot be divided. The Savior and Lord are one. When the apostles preached they proclaimed Christ to be Lord. To bow to his rule was never presented in the Bible as a second step of consecration. 'For we preach not ourselves, but Christ Jesus the Lord; and ourselves your servants for Jesus' sake' (2 Corinthians 4:5).
When sinners truly receive him they do receive him as Lord. 'As ye have therefore received Christ Jesus
the Lord, so walk ye in him' (Colossians 2:6).