I've received a few questions about my Father's Day sermon on Hebrews 3:7-14.  This is one of the passages of Scripture that deals most directly about a doctrinal subject known as "assurance of salvation" – how someone can know whether or not they are saved.  It is also a notoriously difficult doctrine to grasp conceptually, so questions are very understandable (and I'm always thankful for questions - then I know you're listening).

In that sermon, I said the following (this is copied from my sermon manuscript): 

So if in the future it's possible that our hearts can become hard and we can turn away from God, does that mean that we can't really know whether or not we are Christians, because we can't know what our future holds as a Christian?  Well, it depends on what you mean by the word "Christian."  If by Christian, you mean that you know you are "in", no matter what happens in the future, that you can know today that you will go the rest of your life without hardening your heart and turning away from the living God, then no, you can't know that you are a Christian [I went on to state that we can know we are Christians today, by how we live, which is the biblical use of the word]. 

There is no guarantee in the Bible that any currently professing Christian will not one day in the future decide to fall away from the faith (no matter what religious experiences we've had in our pasts).  That's why the author of the book of Hebrews (along with every other New Testament author) repeatedly urges his readers to hold fast to the faith.  That's why he says: "See to it, brothers, that none of you has a sinful, unbelieving heart that turns away from the living God" (Hebrews 3:12).  The whole reason we must "see to it" is that there is a real danger that if we don't, we will fall into apostasy (denying the faith and returning to a life of deliberate sin, where hell awaits us). 

I think the confusion comes in because so many Southern Baptists have heard from preachers something known as "once saved, always saved."  As in: "Once you are saved, you are saved, and that's the end of the matter."  I believe that too, but I also am certain that while God knows with absolute certainty those who are "once saved, always saved," he has not shared that information with us.  It's not like the people going to heaven walk around wearing a scarlet "H" on their chests, while those who aren't go without.  Instead, he commands that we "see to it," "make your hope sure" (Hebrews 6:11), "make your calling and election sure" (2 Peter 1:10), "press on" (Philippians 3:12), and "fight the good fight" (1 Timothy 1:19) every day until we die.   

I have no doubt that much of this confusion has been exacerbated by decades of Southern Baptist preachers exhorting church attenders to keep "every head bowed, every eye closed," while urging others to "walk the aisle," "make a decision," or "pray a prayer," with little or no follow up or discipleship done after the decision.  We have been urged to "settle the matter tonight," when the Bible clearly teaches that can't be done over the course of one night.  Rather, the only way to "settle the matter" is to live faithfully for Jesus and fight sin until we die.

Friends, we don't just need to make a decision for Christ once during a revival, but dozens of times every day, and each day until we die.  We must make it our life to fight sin every day with the faith that God through Christ will meet all our needs perfectly and fill our hearts with heaven-saturated joy.  In short, we must decide to "see to it," all the while confident of this: "Work out your salvation with fear and trembling, for it is God who works in you to will and to act according to his good purpose" (Philippians 2:12-13).