Can a believer change his core beliefs?

Question:  The other night I had a conversation with some people that dwelled around true belief and insincere intentions. One party was of the opinion that a person’s core beliefs, whatever those are, are the beliefs that compose a person’s morality and are unchanging and cannot be gained or lost through action. As if, you might say, whatever you might act upon, those actions reflect your true beliefs. If then, a person was to act contradictory to what their previous beliefs had supposedly been-those beliefs were merely insincere intentions and not true convictions. An obvious rabbit trail that followed was belief in God, and salvation. One party was of the opinion that salvation, if genuine, could not be lost. In a scenario where a person might recant their once held convictions concerning God, it was determined by one party that those prior convictions were, as I said earlier, merely insincere intentions. I would be very interested to know your personal feelings on this matter.

Answer: When we act against core beliefs, we are miserable with guilt. This demonstrates that they are not insincere intentions and that the only way to have any joy in life is to continue to act according to our sincere intentions, our core morality. Can a person’s conscience become dulled and no longer sensitive to his core morality? Yes, and in this case, we might conjecture that his core morality has changed.

But with regard to salvation, the Bible seems to indicate that once you have been redeemed by Christ through faith in Him and His provision for your forgiveness, the new core of you is something placed there by God that He will ensure remains and grows (1 John 3:9, for example). This does not absolve us of responsibility to maintain the health of our new core. The author of Hebrews asserts that true believers are disciplined by God in order that we might share in His holiness (12:10). So we are to make every effort to be holy because without holiness no one will see the Lord (12:14). If someone who has professed to be a believer demonstrates through his actions and/or beliefs that he has abandoned this core, it suggests that he may not be a believer in fact. If the discipline of the church and of God (they are considered of equal authority by Jesus, Matthew 18:15-20) do not serve to turn this person back to the truth, then he is to be considered as an unbeliever (“a pagan or a tax collector”).

Historically, this view has been termed the perseverance of the saints. It holds that true believers cannot lose their salvation, but salvation is evidenced by continuation in the faith. Just because someone says he is a believer does not make it so. He must demonstrate that his core has truly been changed. When he goes against his core, he will be miserable. He will not be able to finally dull his conscience because God will not allow that. God will bring discipline into his life to turn him back to holiness.