One of the items of contention in Christian theology is whether someone can become unsaved. The P in the Calvinist TULIP is perseverance of the saints, or "once saved, always saved" in evangelical folk phrasing.
In that setting, someone who walks away from the faith either (a) is still saved anyway or (b) never really believed in the first place. I find the second option to make more sense.
There are passages in the Bible that point to the idea that not everyone who appears to be a believer is; they have to believe it in their hearts as well as verbally profess it, which leaves open the prospect of someone mouthing statements of faith but not really buying in.
The alternative to that is that you can lose your salvation. A legendary piece of New England graffiti in praise of Boston Bruins star Phil Esposito was "Jesus saves...and Espo scores on the rebound", figuratively getting the puck past the Goalie Host.
The idea that salvation is a work in progress that only gets nailed down at death is a common thought in churches with a Wesleyan heritage as well as Campbellite traditions (Disciples of Christ, Churches of Christ, generic Christian churches). As I understand it, Catholic doctrine also sees salvation that way. There, a baseball metaphor would apply, as a save is recorded only when you finish the game with the lead.
That begs the question to the fearful believer; if that salvation is fragile, what do you need to do to avoid falling away? Is it better to die young before making mistakes that cost you your eternity?
That last one ate at me six years ago at this time when I had lost my teaching job and was looking at a depressing future and going to Tates Creek Christian in Lexington; I recall having to leave a sermon stressing that work-in-progress salvation to contemplate whether I even wanted to continue lest my depression lead me away from God.
The Free Methodist church we go to in Midland is in that insecure-salvation camp, but that isn't always preached in the pulpit. We had a youth in the church who was both active and a committed believer fall prey to psychological issues and committed suicide. The pastor noted that he was sure he was still saved despite that, even though there are schools of thought in the Church that would bar the suicider from Heaven.
I'd like to think that the Goalie Host grabs the puck and prevents any rebound when He makes a save. Paul tells the Romans, "Who shall separate us from the love of Christ?"
That may be a more emotional than intellectual approach to the issue, for an image of security seems more in like with Scripture than a tightrope act over the pits of Hell as we live out our salvation. We are to live that out with fear and trembling, but not to such a point where it becomes debilitating.