Other passages warn of the possibility. "Wherefore the rather, brethren, give diligence to make your calling and election sure: for if ye do these things, ye shall never fall." (2 Pet. 1:10) "But I keep under my body, and bring it into subjection: lest that by any means, when I have preached to others, I myself should be a castaway." (1 Cor 9:27) "Wherefore let him that thinketh he standeth take heed lest he fall." (1 Cor. 10:12)
Perhaps the most notable passage on the subject is the entire book of Jude. He warns of those who are Christians who are leading other Christians into all manner of evil. If it was not possible for them to fall from their saved state, why would he find it necessary to change from what he originally intended to write and instead warn them against something they could not do? “Behold, the Lord cometh with ten thousands of his saints, To execute judgment upon all, and to convince all that are ungodly among them of all their ungodly deeds which they have ungodly committed, and of all their hard speeches which ungodly sinners have spoken against him.” (Jude 14-15) These four repeated instances of “ungodly” are spoken about people who had once been followers of Christ, who had been once saved. They had been ungodly, become godly, and are again ungodly. That seems to be a description of losing one’s salvation. How could an ungodly person be a saved person?
The problem with arguing that you can lose your salvation is that people begin to think that you can easily lose your salvation. That just is not so. Just as Paul told the Galatians that relying on legalistic keeping of the Law of Moses was falling from grace, so also expecting to fall from grace with one sin is believing in legalism. It is believing that God’s grace is unable to save, and that one can save himself by being perfect or lose his salvation by being less than perfect. The only time one sin can cause a person to lose his salvation is his first sin.
Jude may have been writing to warn Christians about those who had turned back from God, but he also said that not all who did so need be lost. “And of some have compassion, making a difference: And others save with fear, pulling them out of the fire; hating even the garment spotted by the flesh.” (Jude 22-23) Even those who have lost, or are in the process of losing, their salvation can be restored.
In 1 Corinthians 5, Paul tells of a man who engaged in incest. It is generally believed that this is the same man he talks about in 2 Corinthians 2:7, “So that contrariwise ye ought rather to forgive him, and comfort him, lest perhaps such a one should be swallowed up with overmuch sorrow.” One who has not turned away from God so much that he will not respond, even an incestuous adulterer, is still a brother. As long as one returns to God, no matter what he has done, he has not lost his salvation.
It is possible to lose one’s salvation. Fortunately, it is not easy. Let us stop giving the impression to others that it is as simple as one sin.