One problem that I have with the idea of perseverance of the saints is my own personal experience. I’ve seen committed Christians lose their faith.
The standard answer is that if they had really been Christians, they wouldn’t have lost their faith. And this does seem to have some biblical backing: “They went out from us, but they did not really belong to us. For if they had belonged to us, they would have remained with us; but their going showed that none of them belonged to us.” (1 John 2:19) Isn’t that what John is saying here?
I’m not so sure. This really seems to be more of a reference to unity in the body than to salvation. 1 John presents continuance in the body as of vital importance; many think that’s what he’s referring to in these verses: “If anyone sees his brother commit a sin that does not lead to death, he should pray and God will give him life. I refer to those whose sin does not lead to death. There is a sin that leads to death. I am not saying that he should pray about that.” (1 John 5:16) Many commentators think that the sin John is referring to is leaving the fellowship (see 1 John 1:5-7)
I know that many people have been convinced that they were in Christ, yet then fell away. “How do you know they were in Christ?” Well, 1 John 5:13 says that someone can have confidence of eternal life. I just can’t see saying that everyone who ever fell was just fooling themselves about their faith.
“But you can think that you are in Christ and not really be in Christ!” Again, this seems to have some backing, reading Matthew 7:21 (a verse that has been strangely popular in some churches). Somehow, I don’t find this “assurance” very comforting. It tells me that I may believe that God has given me eternal life, but be very wrong about it. That’s blessed assurance?
I’ll stick with the confidence that as long as I continue to believe in Jesus and seek the salvation he offers, he will continue to give it to me. That’s the kind of assurance I can base my hope on. “I write these things to you who believe in the name of the Son of God so that you may know that you have eternal life.” (1 John 5:13) That’s what I call blessed assurance