Steaver,
you are right. The faith is very important. What is faith? The Holy Spirit gives it to us. Now let's assume that someone got the faith but later starts to act based on Satan's influence. It's like saying no to God and saying yes to Satan. Is it fair to say that the person is losing the faith. What if it gets to the point that the person loses the faith completely. Is it possible? Do you know somebody that fits this scenario?
I don't think it is fair. Scripture teaches it is not possible for someone to lose "saving faith" which is a gift from God and not of ourselves.
Christians can have a broad degree of faith. Faith which is developed over their lives through trails and tribulations, also developed through fellowship and study of God's Word. This faith can range from very little faith to great faith.
Even those which appear to have the greatest faith, in God's eyes have practically nothing. Have you ever seen a Christian say to a mountain "move" and it did?
"And Jesus rebuked the devil; and he departed out of him: and the child was cured from that very hour.
Then came the disciples to Jesus apart, and said, Why could not we cast him out?
And Jesus said unto them, Because of your unbelief: for verily I say unto you, If ye have
faith as a grain of mustard seed, ye shall say unto this mountain, Remove hence to yonder place;
and it shall remove ; and
nothing shall be impossible unto you ." (Matt 17:18-20)
I believe the mustard seed is one of the tiniest seeds there are and it is why Jesus used it as an analogy. So measure your faith by how often you can move mountains and you will see that if not for God preserving the born again through His power we would all be doomed!
How much faith do you believe it takes to be saved and how do you measure that faith? Are you using what Jesus used, moving mountains? Remember, what measure ye mete, It shall be measured to you again. (Matt 7:2)
I do not know anyone who fits the scenario you have discribed. I know many who have greived the Holy Spirit of God, whereby they have been sealed unto the day of redemption (Eph 4:30) and have shipwrecked their faith (1Tim 1:19). But even a wrecked faith is still faith.
"For we must all appear before the judgment seat of Christ; that every one may receive the things done in his body, according to that he hath done, whether it be good or bad." (2Cor 5:10)
God Bless!