This "Carnal Christian" teaching was invented to accommodate all the supposed converts of modern evangelism. The non-lordship teachers had to have some explanation for the thousands and thousands of those who are products of an evangelism that leaves out Bible repentance from their evangelistic message. I am referring to those who make "decisions," walk aisles and make professions of being Christians, but their lives have never been changed by the power of the Holy Spirit. Therefore, they do not love what Christians love and hate what Christians hate. They act, think and live like non-Christians, but their teachers must have some explanation for their unchanged lives. Thus the unbiblical category "Carnal Christian" was invented by the non-lordship teachers.
