If you have now said "lord, lord", but then reject Christ, you will go to hell. No "oh, I already said it"
Remember the case of the first parents Adam and Eve who held God's grace and then rejected it.
Lastly, remember "See then the kindness and the severity of God: severity toward those who have fallen, but Gods kindness to you, provided you continue in his kindness; otherwise you too will be cut off" - Rom. 11:22
It’s easy to say, lord, lord. Harder to live as He would have us do.
I know you Catholics think someone can lose his salvation, while as Baptists we believe that one who rebels against God was never saved in the first place.
This may be a question of semantics, and I will admit that while I profess “once saved, always saved”, I am somewhat ambiguous about it. I could be wrong, but as it is not a doctrine essential for salvation, I don’t worry about it too much.
Still, it has nothing to do with the existence, or non-existence, of Purgatory.