When I look at certain passages in the Bible it would appear that a believer could lose their salvation.  The problem arises in what we qualify as a believer.  If by believer or Christian you mean a genuine believer—that has a true faith from the heart the answer has to be no.

If you mean someone who claims to be a believer but never really had a true faith then they could also not lose their salvation, because they never truly accepted the gift of salvation from Christ so you cannot lose what you never had.

The question of Christians and lost salvation can be confusing because there are such passages as Hebrews 6:4-6 "(For in the case of those who have once been enlightened and have tasted of the heavenly gift and have been made partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, and then have fallen away, it is impossible to renew them again to repentance, since they again crucify to themselves the Son of God and put Him to open shame."), which seem on the surface to suggest a Christian can lose their salvation I do not believe a true Christian as long as he or she lives in true faith and has accepted Jesus can lose their salvation. 

The first thing we must think about when we are reading any Bible passage is that it is a translation from an original language and as with any translation sometimes the true meaning of the passage gets lost in the translation.  I do not want to get into a long discussion of Greek, but the words translated “fallen away” in the Hebrews passage is the Greek word parapipto, which means to inadvertently fall away. 

In the light of this you can see that the rest of the passage means that when we inadvertently do something wrong or sin we cannot ask again for salvation from Jesus because once we are saved we are saved.  To ask for salvation again is to put to shame what was done for you on the cross by Christ because you feel it did not work the first time.

I think the Parable of the Seed in Mark 4:1-20 is a good illustration of what it means to be a Christian.  The seed that falls in the good soil is the one that grows and flourishes.  If our heart is firmly rooted in the good soil of Jesus Christ we will grow and flourish

The seed that falls on the rocky soil seems to flourish for a little while but because the roots do not run deep the plant will soon wither and die.  This is the person that seems to be a Christian but because they have not put their full faith and trust in Christ they soon fall away from the faith. Sometimes people confuse these people with true heart felt belivers and can make the assumption that a Christian can lose their salvation. The problem is that you can argue these people never had true salvation to begin with.

Also Jesus Himself tells us in John 10:28 “I give them eternal life and they shall never perish and no one can snatch them out of my hand”.  So if we are firmly in Christ’s hands then we cannot be pulled from Him: i.e. lose our salvation.

Again in Ephesians 1:13 Paul talks about those who are born again and are partakers of the Holy Spirit and are in fact sealed by the Holy Spirit.  When we receive the Holy Spirit it is a sign of our true and saving faith in Christ. 

In passages such as the ones Hebrews, Mark, and Ephesians we are told time and again that once we put our trust in Christ and are truly saved, we will always be saved.  And to teach that Christians can lose their salvation is to teach a works based Gospel, which Paul clearly wrote against in Ephesians 2:9, “not by works lest any man boast. “. 

My hope is that these verses help you know that if you have a true and heartfelt faith in Christ and what He has done for you on the cross you have eternal life. There will be times that you may fall or stumble but don’t fret, just get up dust yourself off, go to God in Prayer and get back in the race.