Reformationist said:
Hebrews 6:4-6 is not speaking about the elect of God fully and finally falling away. It is speaking of those who have, by their affiliation with the people of God, tasted His special graces and chosen, in spite of that, to continue in their sin.
You are reading something into this passage that isn't there. These people
were "once enlightened", they "tasted the heavenly gift", and were "partakers of the Holy Spirit". V.4
1. What is the "heavenly gift"? Justification! Meaning, Christ died for them.
2. You can't experience these things without being called by God. In other words, how could one be filled with the Holy Spirit without being justified, and how could one be justified, but not saved?
As you can see from the immediate context, the author distinguishes between those that do fall away and those he knows will hold fast:
Hebrews 6:9
Though we speak in this way, yet in your case, beloved, we feel sure of better things--things that belong to salvation.
No, this thought is just simply disclosing Paul's "confidence" in the people that he was addressing, thus giving them the benefit of the doubt that they wouldn't turn out to be like those who fell away from the faith.
I mean really, would you expect Paul to say, "I am confident that you people will be among those who have fallen away"? Paul was an optimist, not a pessimist, and here he is once again, as he has done in other places, demonstrating his optimistic nature.
Besides, if they couldn't fall away, what sense would there have been in him saying, "Therefore do not cast away your confidence, which has great reward. For you have need of endurance, so that after you have done the will of God, you may receive the promise..." Heb. 10:35-36
Now, here he is implying that it is possible to fall away. And this is in harmony with what Jesus taught regarding this issue when He had said, "But he who endures to the end shall be saved." Matt. 24:13
And if you weren't saved to begin with, how could you even endure for but a moment?
But catch this...
Here is Paul's optimism again: "But we are not of those who draw back to perdition, but of those who believe to the saving of the soul." Heb. 10:39
By the way, if they are already saved prior to their existence, what sense would there be in Jesus and Paul talking about enduring so that they might be saved?
And what sense would there be in Paul saying, ""my heart's desire and prayer to God for Israel is that they may be saved." Rom. 10:1
If Paul really believed in your version of the doctrine of predestination it would have been totally unnecessary for him to have said this, since his prayers would do nothing for these people, because their fate was already decided even before they were born.
You see, it is best to keep these things in their proper perspective. If we go by what you are saying, then Paul was a very confused man, since he contradicted himself so many times. But Paul didn't contradict himself at all. You just don't understand what he really meant.
And this is not surprising since even Peter admitted that Paul's thoughts were sometimes hard to understand. 2Pt. 3:16
I am familiar with his admonishments to hold fast to the faith, however, I am not aware of any area wherein he warns against them suffering eternal damnation. Maybe you could help me out by citing a passage in which he does so?
But is this not a given? If they don't hold fast, or endure to the end, do you honestly think that they will still receive the reward?
You see, I think the problem with your theology lies in the fact that you are not putting the threefold nature of sin into perspective.
We are not just saved from the guilt of sin, but we are being saved from the power of sin, and will be, if we endure to the end, saved from the nature of sin.
Thus God does not save us before we choose to be saved. We make the choice, and if we are willing to go through the process, we will be utterly saved.