"If They Shall Fall Away"

"For it is impossible for those who were once enlightened, and have tasted the heavenly gift, and have become partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, if they fall away, to renew them again to repentance, since they crucify again for themselves the Son of God, and put Him to an open shame." (Heb. 6: 4-6 nkjv)

The "if" of this verse is a hypothetical "if," that is, "if" it be in the text at all (pun intended).  

Many times in debate on the question about "losing salvation" I have used this same kind of hypothetical if, such as when I say "if a born again child of God could lose his salvation, then..." This is the same as did Paul in our verse. It is an "if" of logic and reason. But, really, the word "if" is not in the original. It is implied, however. "Καὶ παραπεσόντας and (in spite of this) have fallen" (Meyer) But it makes no difference for the thought is the same. The central question is this: Is Paul describing an actual case or an hypothetical? 

Paul is saying "it is impossible for one who was once truly saved and then lost that salvation to ever be saved again." But, such a statement does not require us to believe that Paul is describing an actual case. And the same thing may be said without the use of the word "if." But, who among those who believe one can lose actual salvation, believes that such a one cannot be saved again? None. But, Paul affirms that if it were true that genuine believers could lose their salvation then they could never be saved a second time. It is arguing reductio ad absurdum, showing the absurdity and falsity of a proposition by showing its logical consequences. Commented Albert Barnes:

"If they shall fall away - literally, "and having fallen away." "There is no if in the Greek in this place - "having fallen away." Dr. John P. Wilson. It is not an affirmation that any had actually fallen away, or that in fact they would do it; but the statement is, that "on the supposition that they had fallen away," it would be impossible to renew them again. It is the same as supposing a case which in fact might never occur." 

There is no doubt that the description Paul gives of believers is that of real believers. There is no way that such a description describes pretenders.

Said Spurgeon (See here):

"First, then, we answer the question, WHO ARE THE PEOPLE HERE SPOKEN OF? If you read Dr. Gill, Dr. Owen, and almost all the eminent Calvinistic writers, they all of them assert that these persons are not Christians. They say, that enough is said here to represent a man who is a Christian externally, but not enough to give the portrait of a true believer. Now, it strikes me they would not have said this if they had had some doctrine to uphold; for a child, reading this passage, would say, that the persons intended by it must be Christians. If the Holy Spirit intended to describe Christians, I do not see that he could have used more explicit terms than there are here. How can a man be said to be enlightened, and to taste of the heavenly gift, and to be made partaker of the Holy Ghost, without being a child of God? With all deference to these learned doctors, and I admire and love them all, I humbly conceive that they allowed their judgments to be a little warped when they said that; and I think I shall be able to show that none but true believers are here described."

That is my view exactly. Spurgeon said:

"But some one says, "What is falling away?" Well, there never has been a case of it yet, and therefore I cannot describe it from observation; but I will tell you what I suppose it is. To fall away, would be for the Holy Spirit entirely to go out of a man—for his grace entirely to cease; not to lie dormant, but to cease to be—for God, who has begun a good work, to leave off doing it entirely—to take his hand completely and entirely away, and say, "There, man! I have half saved thee; now I will damn thee." That is what falling away is." 

If the six experiences of saved people (as Spurgeon showed in the sermon) do not keep a man saved, then he can never be saved. 

"It is impossible for those who have been made immortal and who (nevertheless) died to ever be made immortal again."

The example above is similar to the text in Hebrews and it is not affirming that immortals actually die (for this would not be possible if they are immortal) but only in an hypothetical case. Another example would be:

"It is impossible for the one who is God, and became no god (lose his divinity) to become God again." 

Again, the case is hypothetical, a manner of reasoning about the absurdity of a given proposition. The proposition that is absurd in its logical consequences is one that says that there is such a character as loses his salvation.

Rather than the verse teaching that truly born again children of God may lose their salvation it affirms just the opposite. Don't you see?