I just chatted with a young lady that I hadn't talked to in a couple years, and to my chagrin she has gotten involved with a "Community Church" thingamajig. You know the drill: gotta' learn Greek, no final authority but God, no eternal security, speaking in tongues, healing, the whole bit.
My question to her, which she was unable to answer (even though she's attending "Bible" school through her church), was simply "where does the Bible say that a person can rescind their salvation?" (Ok, I didn't use exactly those words, but it's the same idea.)
First thing, people that believe like she does have no clue what the New Birth of John 3 means. They don't understand that people are reborn into God's Image, the Image that Adam lost by his disobedience. Jesus, the LAST ADAM, retrieved that Image by His obedience, allowing us to again be "made in His image." Not since Adam's sin, until the death and resurrection of Jesus Christ, had anyone been "reborn." Jesus hadn't paid the penalty and retrieved the crown of the Kingdom of God (spiritual) yet!
Secondly, they have no idea about Spiritual Circumcision. It's laid out so clearly in Scripture, but their belief in optional Security prove that they have no clue about predestination to the conformation of Christ or what the "operation of God" is in Colossians 2:12.
Note: every time Paul says "I would not have ye to be ignorant, brethren," the brethren are ALWAYS IGNORANT!