Does God forgive sin in advance? I know Christ died for sins “once and for all,”1 Peter 3:18-but I have been speaking with several self-identified Christians who believe the current and future sins they engage in are covered by the death of Christ, so they do not worry about their sins very much (it seems to me)?
In answering your question it may help to understand what it means to put one’s faith in Christ. What precisely is one accepting when they believe in Jesus?
Millard Erickson’s explanation of original sin can help us in understanding this:
“What is the nature of the voluntary decision which ends our childish innocence and constitutes a ratification of the first sin, the fall? … We become responsible and guilty when we accept or approve of our corrupt nature. There is a time in the life of each one of us when we become aware of our own tendency toward sin. At that point we may abhor the sinful nature that has been there all the time. We would in that case repent of it and might even, if there is an awareness of the gospel, ask God for forgiveness and cleansing … But if we acquiesce in that sinful nature, we are in effect saying that it is good. In placing our tacit approval upon the corruption, we are also approving or concurring in the action in the Garden of Eden so long ago.” (Introducing Christian Doctrine)
So faith in Christ is about accepting our need (that we are a sinner) and turning to God for forgiveness and salvation. So it seems nonsensical that someone could put their faith in Christ but continue in their sin. In that case they have not really accepted that their nature is corrupt…they endorse it.
It is true that if someone is forgiven, then they are forgiven of what they are (a sinner). Thus there can’t be particular sins for which they are not forgiven if God has forgiven them. At the same time, however, if someone pursues their sin rather than pursuing God then this is evidence that they have not put their faith in Jesus.
Chapter Director, Reasonable Faith
Master of Arts in Apologetics,
Luther Rice University and Seminary