Remain on your toes MFR, don't mistake the offer or promise, for the conclusion. Where your convictions stand on your death bed, is where the conclusion lies, Whisper quoted only the offer. God has promised eternal salvation to those who repent and bow down to Christ Jesus as Lord & Saviour, i.e. forgiveness is conditional. If forgiveness is contingent upon one, first, hearing the Word, then understanding what was preached (depending on the evangel who explained the good news), and then accepting the Gospel of Christ, then one's procurement of their salvation is only as solidified as far as their understanding and convictions go. 'some seeds fell by the shallow ground, took root for a moment (accepted it at the time), then fell away'. Can one say 'yes' to Christ today, then tomorrow deny him and remain saved, ...how does that work?
This is why we never let our guard down, we study often to resist falling away, which the devil will not relent.
Don't mistake the promise for the status, God promises to protect you and to not let you be stolen from his hands, but that just means that he's on our side working for us, it does not mean that we can sleight or defy him and that he won't let us go. It means if we try, he will protect us, and that we can rely on him in times of our trouble, persecution and doubt, ...but not our rejection, regardless of where we stood in the past.