Christian answering questions.

[PETE_ROSE]

I suspect he's referring to John 15:6... but the broader context is in Hebrews 6:4-6.

4 For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost, 5 And have tasted the good word of God, and the powers of the world to come, 6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.

Unfortunately, the verses don't say that a person was never saved. Verse 4 specifically says, "were once enlightened and have tasted of the heavenly gift", implying that they were saved, but are now considered unsaveable... and in a lot of trouble with God.

I am unfamiliar with any other verses that give an actual implication that a person who is no longer a believer was never in fact a believer. Perhaps I have missed something. I would be delighted to be enlightened.

(Edit to Add: He may be referring to the whole "no one can snatch them out of my hand" bit--I forget that verse. But I'm pretty damned sure it's referring to believers being unable to be saved through Jesus because of other Powers, not to it being impossible to have once been a believer and then cease to believe.)

I believe John 10:29 is what you were referring to.  My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father's hand.

Looks like I would also agree with everything you said as that is near exactly what I discern in the passage found in Hebrews 6.  I would add that in John 10:29 it appears the implication to be that no man (other than yourself) is able to pluck them from the Father's hand.