Can your sins cause you to fall from grace?

Writing to the Philippians, Paul says, "He who has begun a good work in you will perfect it to the end" (Phil. 1:6). Therein is the promise of God that what He starts in our souls, He intends to finish. So the old axiom in Reformed theology about the perseverance of the saints is this: If you have it—that is, if you have genuine faith and are in a state of saving grace—you will never lose it. If you lose it, you never had it.

We know that many people make professions of faith, then turn away and repudiate or recant those professions. The Apostle John notes that there were those who left the company of the disciples, and he says of them, "Those who went out from us were never really with us" (1 John 2:19). Of course, they were with the disciples in terms of outward appearances before they departed. They had made an outward profession of faith, and Jesus makes it clear that it is possible for a person to do this even when he doesn't possess what he's professing. Jesus says, "This people honors Me with their lips, but their heart is far from Me" (Matt. 15:8). Jesus even warns at the end of the Sermon on the Mount that at the last day, many will come to Him, saying: "Lord, Lord, didn't we do this in your name? Didn't we do that in your name?" He will send them away, saying: "Depart from Me, you workers of iniquity. I never knew you" (Matthew 7:23). He will not say: "I knew you for a season and then you went sour and betrayed Me. No, you never were part of My invisible church." The whole purpose of God's election is to bring His people safely to heaven; therefore, what He starts He promises to finish. He not only initiates the Christian life, but the Holy Spirit is with us as the sanctifier, the convictor, and the helper to ensure our preservation.
True Christians can have radical and serious falls but never total and final falls from grace. —R.C. Sproul

I want to stress that this endurance in the faith does not rest on our strength. Even after we're regenerated, we still lapse into sin, even serious sin. We say that it is possible for a Christian to experience a very serious fall, we talk about backsliding, we talk about moral lapses, and so on. I can't think of any sin, other than blasphemy against the Holy Spirit, that a truly converted Christian is not capable of committing.

We look, for example, at the model of David in the Old Testament. David was surely a man after God's own heart. He was certainly a regenerate man. He had the Spirit of God in Him. He had a profound and passionate love for the things of God. Yet this man not only committed adultery but also was involved in a conspiracy to have his lover's husband killed in war—which was really conspiracy to murder. That's serious business. Even though we see the serious level of repentance to which David was brought as a result of the words of the prophet Nathan to him, the point is that David fell, and he fell seriously.

The apostle Paul warns us against having a puffed-up view of our own spiritual strength. He says, "Therefore let anyone who thinks that he stands take heed lest he fall" (1 Cor. 10:12). We do fall into very serious activities. The Apostle Peter, even after being forewarned, rejected Christ, swearing that he never knew Him—a public betrayal of Jesus. He committed treason against His Lord. When he was being warned of this eventuality, Peter said it would never happen. Jesus said, "Simon, Simon, Satan would have you and sift you like wheat, but I have prayed for you, so that when you turn, strengthen the brothers" (Luke 22:31).Peter fell, but he returned. He was restored. His fall was for a season. That's why we say that true Christians can have radical and serious falls but never total and final falls from grace.

I think this little catchphrase, perseverance of the saints, is dangerously misleading. It suggests that the perseverance is something that we do, perhaps in and of ourselves. I believe that saints do persevere in faith, and that those who have been effectually called by God and have been reborn by the power of the Holy Spirit endure to the end. However, they persevere not because they are so diligent in making use of the mercies of God. The only reason we can give why any of us continue on in the faith is because we have been preserved. So I prefer the term the preservation of the saints, because the process by which we are kept in a state of grace is something that is accomplished by God. My confidence in my preservation is not in my ability to persevere. My confidence rests in the power of Christ to sustain me with His grace and by the power of His intercession. He is going to bring us safely home.