Some churches view salvation differently, but from a scriptural standpoint it's when you commit your life to Christ! Of course in order to make the commitment there are certain things entailed" 1) Admit one's sins, 2) feel sorrow for sinning, 3) believing in Jesus, 4) accepting Jesus' sacrifice of himself on the cross in your place, 5) repenting to Jesus of your past sins, 6) a public testimony of your salvation entailing baptism and 7) living as much like Christ as can be done. Shortcuts to salvation are ineffectual! That all flies in the face of of scripture and is called "Calvinism".
Sure, God's grace is why we're saved and are free, but we still participate in being saved. It's not just a day when we realize that we have been elected and we can't even resist it! It's a day when we, encouraged by the Holy Spirit "do" things such as exercising our god-given free will!
"Backsliding" is when a Christian isn't living as Jesus would have him live. If asked the backslider will say "I believe in Jesus, but have trouble living a Christian life!" Most backsliders appear to be the epitome of unsaved sinners. Perhaps some, if not most, are! Calvinists believe in "preservation of the saints". That means "once saved always saved" and allows nothing for free will. Saved people are predetermined by God before they're ever born, cannot accept or refuse salvation, do nothing toward responding to God, and frankly, they don't even have to live a Christian life! Neither can they freely choose to remain a Christian. They are forced to go to heaven!
Many Baptist churches teach "once saved always saved". That's a ticket to go ahead and sin and still be a Christian. It shows little faith and no responsibility to live Christlike. At most it's "fire insurance" to keep one out of hell, but realistically it's fire insurance issued by a fraudulent insurer. The person believes they're insured until the day the "house burns" and find out that their claim is denied!
Matthew 7:23 "And then will I profess unto them, I never knew you: depart from me, ye that work iniquity (sin)."Yes, backsliding exists, but it's not of long duration. It's not a lifelong endeavor! What I mean is that many people who're "saved" never ever live righteously and sin flagrantly. The "old person" was never drowned with baptism and the "new person" was never raised up. Those people go through the motions, but there is never a heartfelt guilt nor sorrow, let alone repentance. All that is left is a wet sinner. Most people who are called "backsliders" are lost to eternity!
1 John 3:9 "Whosoever is born of God doth not commit sin; for his seed remaineth in him: and he cannot sin, because he is born of God."There are three ways to look at this in all honesty: 1) A Christian's sin is never counted against him, 2) Christians never sin at all, or 3) Christians endeavor to live a holy life and because they seek righteousness, God is gracious enough to overlook occasional sins. I believe it's the latter. His grace is sufficient to cover intentional sin, but it's a race we're running! We are to persevere until the end.
A second type of "backsliding" are those who once believed, but no longer do. They were sincere in their born-again experience, but their faith was robbed by the encroachment of Satan. God puts a hedge around them, but for some reason God allows Satan to pester Christians. That resistance to temptation is how that Christians show that we love him and it's called "works". If we love him, we keep his commandments!
Some Christians fall to temptation. It starts out with little sins and continues until one lives a life as if God's will is important. Their quest for pleasure snuffs out their belief in God. Sometimes it's a false doctrine which deceives them. Whatever, the reason they leave God, that's apostasy and for that there is no cure. Those people become reprobate:
2 Corinthians 13:5 "Examine yourselves, whether ye be in the faith; prove your own selves. Know ye not your own selves, how that Jesus Christ is in you, except ye be reprobates?This is how that you know if you're still a Christian or ever were one. You examine yourself! Do you still pray sincerely, still love God and others, still testify to others and fulfill "The Great Commission"? Is your life more on pleasure than on God. Do you question scripture? Do you ignore scripture? Do you feel hatred for those who talk about Christ around you? There are many other tests; just examine yourself.
If you confess belief, but have no works, some say that you have "back-slidden". Be careful to test whether you were ever born again. There are many who will roast for eternity because they fail to examine themselves in a truthful manner. Also, if one has back-slidden should they not eventually return to Christ? Most don't or so it seems!
"Giving up on God" (apostasy) is extremely dangerous! Here's what is said about those who once believed, but now don't:
Hebrews 6:4-6 (ESV) "For it is impossible, in the case of those who have once been enlightened, who have tasted the heavenly gift, and have shared in the Holy Spirit, and have tasted the goodness of the word of God and the powers of the age to come, and then have fallen away, to restore them again to repentance, since they are crucifying once again the Son of God to their own harm and holding him up to contempt."In short, if you were a Christian, but backslid until your death, there is nothing more to cover you because to do so would be re-crucifying Christ! That can't be done because he died to save us once and for all! Backsliding unto death IS apostasy!