Last Update: 4/1/10 - Added discussion on Hebrews 6:4-6 and on Free Will.
A key doctrine to the Christian faith is "once saved, always saved," which basically means that you don't earn your salvation. You accept it.
Luke 8:13 and Hebrews 6:4-6 are used by some to "prove" that you can lose your salvation. These verses are the most common ones that are used by the opposing point of view, that you can lose your salvation.
Luke 8:13 (New American Standard Bible)
13 "Those on the rocky soil are those who, when they hear, receive the word with joy; and these have no firm root; they believe for a while, and in time of temptation fall away.
However, Luke 8:13 means that the person believed intellectually. They had no root, which means they had no salvational faith. Those who believe that you can lose your faith, latch onto "believe" but ignore "root." You don't lose your faith like you lose keys (oops, I dropped them). You lose your faith like you lose the lottery (you think you'll win, but you don't). Except faith is easier than the lottery, cuz you're just accepting a gift that changes your life. =^)
Luke 8:13 is very difficult to interpret out of context, so the person who uses it to teach that you can lose your faith... has chosen an interpretation that makes sense to him. Then he might "back it up" with a bunch of verses that say absolutely nothing about the subject. But there is one other that we should evaluate...
Hebrews 6:4-6 (NIV)“For it is impossible for those who were once enlightened, and have tasted the heavenly gift, and have become partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, if they fall away, to renew them again to repentance, since they crucify again for themselves the Son of God, and put Him to an open shame.”
So why isn't this one talking about Christians who fall from their faith?
Well, for starters, I think there are so many people claiming to be Christians but don't have true faith... that I divide Christians into buckets of "Saved Christians" and "Unsaved Christians." (Basically this is the same as "True Christians" and "Fake Christians," but I think fake Christians are so much the majority and the "norm" that they are becoming the "true Christians" because that is what Christianity has become... a lack of saving faith. So right off the bat I would say that most Christians don't have faith... only Saved Christians (the minority) do. (Yes, this is very pessimistic, but I've had the fortune of watching so many of my students prove that they aren't saved that it has turned me into an "intense Bible thumper who has a ton of fun, but as soon as we open the Bibles, I become as serious as a heart attack" - what's in quotes comes from my former students.) - Why even mention all this? Because I use the term from now on to differentiate between the two types.
Next up, we need to take a look at the words being used. They actually help prove that this isn't a Saved Christian. First, the word "enlightened" never means "saved." It only means "aware of." So the use of this word purposefully implies by the author that this is not a Saved Christian. Also, it is important to note that this person believes that God exists. However, even the demons believe in the existence of Christ (and tremble before Him, as we all will).
Second, the word "tasted" also implies someone who has tasted from the cup without drinking. This is someone who has seen the proof of Jesus Christ through the love, teaching, and miracles to be found in the church today (and if you haven't seen these three things in your church, you might want to find a church with more Saved Christians who are on fire for Jesus). Now, once you drink, you believe. But if you taste, you are dipping your feet in the water without jumping in. Faith is very clear. You must jump in or you are not a Saved Christian.
For further proof of the second point, Hebrews 2:9 (the same book as this one) says that Jesus tasted death. So if these Christians ever tasted the heavenly gift of life, then they never obtained it (and never became Saved Christians). Similarly, Jesus iS not dead. He merely tasted death. The author is using these terms consistently. So either this person described in Hebrews 6:4-6 is an Unsaved Christian or Jesus is still dead today. We must pick one.
Luke 8:13 and Hebrews 6:4-6 are the two passages that could be interpreted that way (but shouldn't be). Even if they are interpreted to mean that you lose your salvation, it should be contrasted with the dozens of verses that say you can't lose your salvation. The following verses are examples that explain that you can't lose your salvation.
Look up Matthew 13:3-23 (many Christians will receive the gospel and think they are saved, but they aren't), John 10:28-29 (no one can snatch people of Christ's hands; you can't even snatch yourself out of His hands), John 5:24 (the choice is made once for your entire life), Ephesians 2:8 (the gift implies that you receive it before the works, and not after), 2 Corinthians 5:17 (when you have faith, you are no longer the same person), Romans 8:33 (God chose us), Romans 8:35 (once we are chosen, nothing can separate us), Romans 8:38-39 (not even life, demons, or anything in creation can separate us from Christ; you are part of creation), 1 Peter 1:4-5 (faith shields you until salvation... even from yourself), Philippians 1:6 (when God begins working on your faith, He will continue all the way to Heaven), Romans 2:29 (faith is like circumcision; once for life), Romans 8:14-16 (faith and receiving the Spirit are adoption; done for life), Romans 15:16 (the Holy Spirit sanctifies us through faith as a sacrifice/offering to God; a sacrifice is permanent), and John 3:16 (if you believe, then you don't perish; believing and then perishing contradicts this verse that is the cornerstone of the Gospel).
One more thing to discuss... Free Will. This is a huge monster, so I won't give it the detail it deserves here, but it is a good point. If Free Will exists, then we should be able to choose not to be saved anymore. Makes sense. Right?
Well, the flaw is in the setup. Yes, and an all loving God can't send people to hell. However, the flaw is in the setup. God is loving, but He is more just than loving, and hell is just. If you commit murder, you pay by going to jail. That's justice. Likewise, if you sin, you deserve destruction. That's justice. You pay for your crimes.
Now back to Free Will. It doesn't exist. How can it? How can God choose us if free will exists? And likewise, all these passages about salvation above are also nullified if we can choose to walk away from God at any one time. And the Bible is then a hodgepodge of inconsistencies.
The Bible never mentions anything remotely similar to Free Will. We just created that doctrine out of our own desires for Free Will to exist. The closest the Bible ever says to that doctrine is when it implies that we are able to make our own choices. The Bible doesn't even directly say that we are able to make our own choices. It merely implies that, so even that doctrine (that we can make our own choices) isn't all that important (but it does exist in Scripture, nonetheless).
But don't we get to make our own choices? Yes, otherwise we'd be robots and useless to God. God wants us to be His servants, friends, and adopted children... not robots. Otherwise, why does faith exist?
So here is what the Bible shows... God allows us to make choices. So we don't have Free Will. We have Decision Permission. God gives us His almightly permission to make most of our own decisions. However, sometimes He makes decisions for us.
That makes sense, doesn't it? When an earthquake occurred, people died. Not one of them chose that death. They lived there, but they would have moved had they known. God allowed that to happen. And He caused it to happen when He formed the earth we corrupted when we fell. I think about how the economy crashed, I got laid off, my basement flooded, and my rental house dropped so low in value that it was cannibalizing our finances (and all that happened back to back). Totally not my decision. He gave me the strength to survive.
God can (and has) at any time made up our minds for us. He can do this by changing our hearts and minds (He did this with Pharaoh, for example), and He can also be very persuasive in forcing us to do His will if He wants to (Jonah was eaten, Job was attacked by Satan, Paul was blinded, Moses complained when God first told him what to do, etc.). And, knowing God is perfect, I'd want Him to do that as much as possible. I trust Him. Although I do hope that He doesn't allow Satan to crush my children. That would be no-good-tastic.
In conclusion, you can't lose your faith. However, you can (1) Never have faith and think you do and (2) Have faith and still choose a horrible sin.