Hebrews 6
1 Therefore leaving the principles of the doctrine of Christ, let us go on unto perfection; not laying again the foundation of repentance from dead works, and of faith toward God,
2 Of the doctrine of baptisms, and of laying on of hands, and of resurrection of the dead, and of eternal judgment.
3 And this will we do, if God permit.
4 For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,
5 And have tasted the good word of God, and the powers of the world to come,
6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.
To whom does Hebrews 6 apply?
The correct answer IMO does not contradict OSAS.
My opinion is that it applies to those who hear the gospel, are convicted of sin by the Holy Spirit, given a foretaste of forgiveness of sin and its joy yet back away, do not accept Christ and do not enter into the "Sabbath" rest of God, Jesus Christ Himself being the true Sabbath rest.
Hebrews 4
9 There remaineth therefore a rest (Grk. sabbatismos) to the people of God.
10 For he that is entered into his rest, he also hath ceased from his own works, as God did from his.
11 Let us labour therefore to enter into that rest, lest any man fall after the same example of unbelief.
Matthew 11:28 Come unto me, all ye that labour and are heavy laden, and I will give you rest.
Here are a couple of examples of those who fall away (perhaps) in this manner:
Acts 24
24 And after certain days, when Felix came with his wife Drusilla, which was a Jewess, he sent for Paul, and heard him concerning the faith in Christ.
25 And as he reasoned of righteousness, temperance, and judgment to come, Felix trembled, and answered, Go thy way for this time; when I have a convenient season, I will call for thee.
26 He hoped also that money should have been given him of Paul, that he might loose him: wherefore he sent for him the oftener, and communed with him.
27 But after two years Porcius Festus came into Felix' room: and Felix, willing to shew the Jews a pleasure, left Paul bound.
Acts 26
19 Whereupon, O king Agrippa, I was not disobedient unto the heavenly vision:
20 But shewed first unto them of Damascus, and at Jerusalem, and throughout all the coasts of Judaea, and then to the Gentiles, that they should repent and turn to God, and do works meet for repentance.
21 For these causes the Jews caught me in the temple, and went about to kill me.
22 Having therefore obtained help of God, I continue unto this day, witnessing both to small and great, saying none other things than those which the prophets and Moses did say should come:
23 That Christ should suffer, and that he should be the first that should rise from the dead, and should shew light unto the people, and to the Gentiles.
24 And as he thus spake for himself, Festus said with a loud voice, Paul, thou art beside thyself; much learning doth make thee mad.
25 But he said, I am not mad, most noble Festus; but speak forth the words of truth and soberness.
26 For the king knoweth of these things, before whom also I speak freely: for I am persuaded that none of these things are hidden from him; for this thing was not done in a corner.
27 King Agrippa, believest thou the prophets? I know that thou believest.
28
Then Agrippa said unto Paul, Almost thou persuadest me to be a Christian.
If this is the case then Hebrews 6 declares:
5 And have tasted the good word of God, and the powers of the world to come,
6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.
This seems to say that having heard the gospel and refused they cannot be be brought back to this point of repentance and be saved having understood the price and would be recrucifying Christ so to speak.
HOWEVER
This passage is prefaced by this declaration as well:
3. And this will we do, if God permit.
In others words it is possible to bring them back to this point if God permits.
I believe Paul was such a one.
HankD