sorry, that is sophistry.
The one who rebels against God and then accepts and then rebels is first called "saved for all them", then "never saved in the first place" and then "saved for all time"
Let's get a few things clear:
Perhaps.
But I recall a young woman when I was in college who switched from Jehovah's Witness to Baptist to Mormon all in the space of the 3 years that I knew her.
Was she truly a believer in anyone of these faiths? I think she was was confused young woman who was just lucky she didn't turn to drugs (at least that I know of).
I knew a man who, according to reports was really religious in his youth. After his mariage broke apart, he became a real horn dog. He once bragged to me that he had slept with over 300 women, that he could remember.
He also became a backstabbing, lying son of a gun. Was he ever truly Christian? I don't know, but if he was, then he will return to Christ before he dies. I don't know that he ever explicitly apostatized.
I'll take HIS word for it that I am secure in Him by simply believing.
John 5:24 Truly, truly, I say to you, whoever hears my word and believes him who sent me has eternal life. He does not come into judgment, but has passed from death to life.
John 10:25-30 25 Jesus answered them, I told you, and you do not believe. The works that I do in my Father's name bear witness about me, 26 but you do not believe because you are not among my sheep. 27 My sheep hear my voice, and I know them, and they follow me. 28 I give them eternal life, and they will never perish, and no one will snatch them out of my hand. 29 My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father's hand. 30 I and the Father are one.