One of our most popular articles concerns losing salvation -- some say you can once be saved, and they become unsaved, others say you can't. Yet that article still generates much of the email we receive.
One of the arguments against once saved, always saved we hear is "if that's true, it means I can live any way I want and still be saved". Not so fast.
Don't interpret the permanence of salvation to mean you can live any way you want and be saved. If people live in perpetual sin that's a clue they might not be saved, no matter what they say. For example, I can say I'm the President all I want, and that doesn't change the facts. Many people may think they're saved, but if they don't have the fruit, their proclamation is worthless.
Another way to look at it is if you ever have eternal life, but then lose it, was it really eternal to begin with? Eternal life is by definition irrevocable. To say otherwise means not only was it not eternal, but God somewhere changed his mind, and that's an area we don't want to go.
The major question isn't losing salvation, but were you ever saved in the first place? That's a more troubling question, and one many don't want to deal with.
You did nothing to earn your salvation (it's a gift from God), so there's nothing you can do to lose it. In short, I know I can't lose my salvation, because I know who I've trusted for it, and I did nothing to earn or merit it. God won't change his mind, and I can't disappoint Him as He already knows all the mistakes I'll make until the day I die.
And He still choose me anyway.

Excellent article.
I find it troubling that many Christians cannot see the obvious disconnect in declaring that salvation is not earned by works, but somehow it is "revocable" by works. The bible makes it quite clear that a person experiencing a genuine conversion is not capable of losing, forsaking or walking away from salvation.
Salvation is a supernatural act - it occurs in the spiritual realm and is not bound by physics, nature or time. This is why it impossible to "lose your salvation" after a time of sin or rebellion - your salvation is written in the book of life, which resides in realm where time is irrelevant.
Some Christians don't like the idea of secure salvation because of people who trample on grace. But this is the nature of freedom and the nature of free-will - just because there is abuse of grace, does not mean we throw it out the window and replace it with a doctrine not found in scriptures. In the same way that people will argue that freedom is bad (people will do bad/sinful things and therefore we need laws controlling morality) people argue against biblical salvation (without the threat of "losing/walking away" from salvation, Christians will trample grace). However it is clearly obvious that grace trampling is not God's fault for first granting grace and freedom - it is the fault of the sinner.
A Christian may sin - but he will also be constantly led to conviction and repentence by the Holy Spirit.