Can someone be a church person and still never have been truly saved?
Yes, it is possible for someone who attends church to never have experienced genuine salvation. Many church people have never had a real salvation experience, lacking the new birth that makes them a child of God. Being religious or church-going does not automatically equate to being spiritually alive in Christ.
Les explains that he has a growing burden for lost people because he realizes how many, even church people, have never had a real salvation experience. The contrast is between those after the flesh and those after the Spirit; the latter have experienced the new birth and are children of God. A carnal mind is enmity against God, so church attendance alone does not prove salvation.