I know what Catholics do when Paul is quoted. Here are Jesus' own words on the subject.
John 10:25-30 25Jesus answered them, "I told you, and you do not believe. The works that I do in my Father’s name bear witness about me, 26but you do not believe because you are not part of my flock. 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. 29My 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."
Well, if you’re referring to “no one will snatch them..” you have likely heard the rebuttal: that this is of course true. But we can separate ourselves. Unless you are a Calvinist, you believe in free will. God does not force us to love Him now or in the future come what may; we may change our minds and hearts as many have.
Now, I still have the question for you, never answered, from a while back:
You said you believe all your future sins are already forgiven whatever they may be. Does this include blasphemy against the Holy Spirit?