1 John 5:11-12 - "And the testimony is this, that God has given us eternal life, and this life is in His Son, He who has the Son has the life; he who does not have the Son of God does not have the life.
As long as we abide in Christ, we have that eternal life that is in Him. But when we choose to no longer abide in Him, we no longer have that eternal life that abides in Him. Many true Christians have chosen to turn back and they not only lose Christ, but they lose the eternal life which is in Him. The New Testament is filled with examples and warnings not to turn back.
1 Tim. 1:5-7; 18-20 " ... some men have STRAYED from these things (that means they HAD the truth, but then turned away from it) ... some men have REJECTED faith and a good conscience and HAVE SUFFERED SHIPWRECK IN REGARD TO THEIR FAITH. Among these are Hymenaeus and Alexander, whom I have handed over to Satan, so that they will be taught not to blaspheme". We are not told if these two men ever came back to the Lord.
1 Tim. 4:1-3 "But the Spirit explicitly says that in later times SOME WILL FALL AWAY FROM THE FAITH, ..." You don't fall away from something that you never had.
1 Tim. 5:8 "If anyone (Paul is speaking of a Christian here) does not provide for his own ... HE HAS DENIED THE FAITH AND IS WORSE THAN AN UNBELIEVER." You don't deny something that you never had.
1 Tim, 6:9-10 " ... those who want to get rich FALL into temptation and a snare ... which PLUNGE MEN INTO RUIN AND DESTRUCTION ... AND HAVE WANDERED AWAY FROM THE FAITH." You don't wander away from something that you never had.
1 Tim. 6:20 "Avoid worldly and empty chatter and the opposing arguments of what is falsely called 'knowledge' - WHICH SOME HAVE PROFESSED AND THUS GONE ASTRAY FROM THE TRUTH." You don't go astray from the truth, if you never had the truth.
2 Tim. 2:12-13 "IF we endure, we will also reign with Him ... " (IF WE DON'T ENDURE, WE WON'T); "IF WE DENY HIM, HE ALSO WILL DENY US; ... "; IF WE ARE FAITHLESS, He remains faithful, for He cannot deny Himself. God is always faithful, but if we deny Him and reject our faith, He is under NO OBLIGATION TO SAVE US. This verse does not say that God is faithful to save someone who walks away from Him.
2 Tim. 2:16-18 " ... Hymanaeus and Philetus, WHO HAVE GONE ASTRAY FROM THE TRUTH ..."
2 Tim. 4:3-4 " ... wanting to have their ears tickled ... AND WILL TURN AWAY THEIR EARS FROM THE TRUTH AND WILL TURN ASIDE TO MYTHS."
If we are genuinely saved, but sometime later we reject Jesus and the gospel, we are NOT FORCED BY GOD TO REMAIN SAVED. If that were true, then every saved person LOSES THEIR FREE WILL - i.e. they no longer have the freedom to reject Jesus - He would be forcing them to stay saved whether they want that or not!
Remember when MANY of His disciples left Jesus? - John 6:66 He turned to the twelve and asked, "You do not want to go away also, do you?" They STILL HAD THE FREE WILL TO WALK AWAY FROM HIM, just like MANY did in verse 66.
That hasn't changed, God will not keep you, IF YOU DON'T WANT TO BE KEPT.
Some say that if you fall away, that you were never truly saved in the first place. That may be true for some people, but not all. Many were genuinely saved and serving and following and abiding in Him - and then, for whatever reason, decide that they no longer want to continue with Him and they turn their backs on Him - and yes, when they turn their backs on the only one who has eternal life, they lose their salvation and eternal life.
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