What Is the “Eternal” Sin?

By Wayne Jackson

“What is the ‘eternal sin,’ mentioned in Mark 3:29?”
Here is the text that is the focus of this question.

“Verily I say unto you, All their sins shall be forgiven unto the sons of men, and whatever blasphemies they shall have blasphemed: but whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin: because they say, ‘He has an unclean spirit’” (Mark 3:28-29).

Jesus Christ is the author of the above warning, and he was speaking to certain Pharisees. In order to see the more complete background of this episode, one must compare Mark’s record with that of Matthew 12:22ff (see also Luke 11:14-23).
On a certain occasion when he was in Galilee, the Lord Jesus encountered a man who was possessed of a demon, with the result that the unfortunate gentleman could neither see nor speak. Christ, by the power of the Holy Spirit (cf. Matthew 12:28), cast out the evil spirit. The people nearby, when they saw the miracle, were amazed, wondering out loud, “Could this be the son of David?” The expression, “son of David,” was the equivalent of “Messiah” (cf. Matthew 22:42).
When the Pharisees observed this excited reaction by the multitude, they bristled with envy (resenting the teaching influence of Jesus). They thus charged: “This man does not cast out demons except by the power of Beelzebub [Satan].” It is important to observe that they did not deny that a supernatural event had occurred. They disputed only the source of power by which the sign was done, transferring such from the Spirit of God to Satan.
There are some very important facts that are essential to understanding the dramatic nature of Christ’s warning about the “eternal sin” in this context.
The sin under consideration was not a mere impulsive exclamation that denigrated the Holy Spirit, i.e., blasphemous words uttered rashly that, once they leave the lips, condemn a person forever — no matter what his disposition in the future.
One must remember this fact. Paul himself had been a blasphemer. In his first letter to Timothy, he conceded that prior to his conversion he was “a blasphemer, and a persecutor, and injurious.” Nonetheless, he received pardon, because his conduct, bad as it had been, was done in ignorance and unbelief (1 Timothy 1:12-14). Can there be any doubt that this persecutor had spoken against the miracles of the Lord, and the Spirit by which they were performed? Later, though, his heart was changed; and the rest is history.
But the case was far different with those Pharisees who were involved in this conflict with the Savior. Note the specificity of Mark’s description of these critics’ actions. The inspired writer describes their conduct in this way: “because they said (elegon — imperfect tense), he has an unclean spirit” (Mark 3:30). The tense of the verb is extremely important. It denotes a sustained activity. It was not a temporary burst of emotion. It was a seething, determined resistance. Professor William Lane comments as follows:

“The use of the imperfect tense of the verb in the explanatory note, ‘because they were saying that he is possessed,’ implies repetition and a fixed attitude of mind, the tokens of callousness which brought the scribes to the brink of unforgivable blasphemy” (p. 146).

Similarly, Edmond Hiebert commented: “Said, looking back to the charge in verse 23, is imperfect tense, marking their persistence in the malicious charge” (p. 102).
When one combines this grammatical fact, with a subsequent comment made by Christ, the point becomes even clearer. Matthew’s record supplements Mark’s account with these stinging words from Jesus. “You offspring of vipers, how can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks” (Matthew 12:34). Some grammatical points are noteworthy.
The phrase “being (ontes) wicked” reflects a present tense participle, and the subsequent verb “speaks” (lalei) also is a present form. The resolute, evil charges against the Son of God were an index to the concrete-like, malevolent quality that encrusted their hearts. These men were not simply making an ignorant mistake. They were deliberate, dug-in enemies of truth. They would hang on to their sinful disposition till the end, and that rebellion would follow them into eternity, hence, an “eternal sin.”
One cannot but be reminded of a comment that the apostle John made regarding those of a similar disposition, “But though he [Christ] had done so many signs before them, yet they believed not on him.” Then, after citing Isaiah’s prophecy (53:1) of Israel’s unbelief relative to its Messiah, the apostle continued, “For this cause they could not believe” (emp. added). Isaiah then was referenced again (6:10), to the effect that the sin underlying their unbelief was hardness of heart (see John 12:37-41).
The “eternal sin,” therefore, was a wicked mindset that followed these hardened rebels into eternity, where an “eternal judgment” (Hebrews 6:2) would be pronounced. Moreover, an “eternal punishment” (Matthew 25:46) of unending remorse would forever haunt them, because there is no post-mortem plan of salvation (Hebrews 9:27).

What About Today?

It is a matter of some consternation that a few sincere, modern writers allege that the “eternal sin” to which Mark referred cannot be committed today. This is a misguided exegetical mistake. Think about the following.
Certainly it is the case that no one today can commit the “eternal sin” in precisely the same way the Pharisees did. Christ is not visibly present on earth, men do not see him performing miracles, and thus one cannot insult the Spirit in an exactly parallel fashion. On the other hand, the following facts must be introduced into evidence.
While we do not have Jesus visibly present today, performing miracles to corroborate the authenticity of his message, there is a modern analogous situation. The documentation of those signs, as recorded in the Gospel accounts, stands as irrefutable evidence of the Savior’s identity. Here is John’s testimony.

“Many other signs therefore did Jesus in the presence of the disciples, which are not written in this book: but these are written, that you may believe that Jesus is the Christ, the Son of God; and that believing you may have life in his name” (John 20:30-31).

Of special significance is the expression “are written.” In the Greek Testament, the verb is a perfect tense form, with this meaning, “that which was written, and remains so.” The perfect form, combined with the present tense, “believing [keep on believing],” underscores the abiding nature of the testimony of John’s Gospel (see Robertson, Vol. V, p. 317).
Professor Wallace says the force is that of “present and binding authority” (p. 576). In other words, the evidence for Christ’s miracles is as compelling today as it was in the first century, due to the integrity of the sacred scriptures. (This case we have argued in many articles on this web site.)
It is a fact, therefore, that the validity of Jesus’ supernatural works (the design of which was to buttress his plan of redemption for mankind) is as strong today as it was in the first century. Why would it not be the case that a hardened repudiation of the New Testament evidence for Christ’s supernatural power, would be the equivalent in this age, to what the Pharisees did during his personal ministry? If a person persistently rejects the New Testament evidence that undergirds the Savior’s credibility, has he not, in principle, exhibited the same attitude and actions the Pharisees did? Has he not committed an “eternal sin”? Is there any other method of redemption available to him? Tragically (for him), absolutely none! Again, we quote from A.T. Robertson.

“[T]he unpardonable sin can be committed today by men who call the work of Christ the work of the devil. Nietzsche may be cited as an instance in point. Those who hope for a second probation hereafter may ponder carefully how a soul that eternally sins in such an environment can ever repent” (Vol. I, p. 282).

C.E.B. Cranfield provided his own barbed comment regarding this matter: “Those who most particularly should heed the warning of the verse today are the theological teachers and the official leaders of the churches” (p. 143).
To this I would add, certainly such is the case with reference to those modernistic “scholars” who attempt to strip the Gospel accounts of their supernatural elements.

Conclusion

There are two final comments that we would make regarding this matter.
First, the absolute terror that this warning strikes in the hearts of people is not the type of approach that someone would use in fabricating a religion that would be popular with the masses. It is not politically/theologically “correct.” This indirectly provides a sense of authenticity to the overall Gospel accounts.
Second, the “eternal sin” narrative contains the sobering caution that we must guard our hearts, so as to keep them always honest, and open to the reception of truth (cf. Ephesians 4:19; 2 Timothy 4:1ff). When one resists the teaching of the Holy Spirit, as conveyed through the sacred Scriptures (cf. Acts 7:51), such can lead to more intense gradations of rebellion (cf. Hebrews 10:29b), resulting ultimately in an eternity of unimaginable horror.
Apostasy rarely comes in “leaps”; Rather, it creeps up by seconds, and those seconds eventually become hours, days, and years. When those years cross the line into eternity, it is too late to remedy the condition.