The following quotation comes courtesy of a reader, from the Bible Dictionary edited by Patrick Fairbairn. (To fill up what was lacking here.)
It’s an elaboration of what I think is the standard view of the nature of the unforgiveable sin in my/our Scottish presbyterian tradition (not that that gives it any more intrinsic worth, but just to put it in context).
“Blasphemy against the Holy Ghost was a sin of which our Lord pronounced those Jews guilty who saw his blessed miracles of love and mercy … and yet shut their minds against all conviction, and endeavoured to ruin his character among those whom they could influence, by alleging that he cast out devils by the prince of the devils.
There was to be noticed, in those who committed this sin, a resolute opposition, in the most obnoxious form, to the convincing work of the Holy Spirit; since they not only resisted the amazing evidence with which he pressed on their attention the divine claims of the Redeemer, but also maliciously and senselessly attributed to Satan the working of the good and gracious Spirit of God; and there was not only the deliberate searing of their own consciences, so that no impression could henceforth be made on them, but there was the desperate determination to involve others in their own intentional perversion of the truth of God in a matter which directly and immediately related to salvation. Hence our Lord declared their sin to be unpardonable, Mat 12:31 etc; Mark 3:28 etc.”
There are about five features in this description which, it would seem, have to co-occur before a person could be said to have committed the unforgiveable sin.
Unless you include the rulers of the Jews at the time of Christ who were so opposed (in this way) to him, as far as I know there aren’t any undisputed examples of people who have committed the unforgiveable sin. It’s sometimes even said that those who were humanly responsible for the crucifixion were later included among those who believed in him (he prayed on the cross, Father, forgive them, and for all we know from the narrative, some of them were converted under Peter’s sermon on Pentecost).
The article in Fairbairn’s dictionary concludes with the observation that “a mystery overhangs the whole of this fearful subject,” and says: “No one, perhaps, is in circumstances to know exactly what this sin is, who has not committed it; while he who has committed it is given over to a reprobate mind, so as never to have any qualms of conscience on account of it, nor any desire to bestow consideration upon it.”
In practical terms, therefore, the function of the report of the unforgiveable sin is to warn, and caution, and provoke those who hear about it to find mercy before it’s too late.
Perhaps it is a result of too-shallow understanding of the nature of sin in its apparently smallest forms, that hinders us from seeking salvation from our sin at the very first opportunity – even if we haven’t committed sins so heinous as to put us in danger of committing the unforgiveable sin, our apparently less serious sins are nevertheless infinitely offensive to the Lord and leave us in a state of condemnation for as long as we remain unforgiven. Why should he forgive any sin? And yet, he does. To persist to the end in an unforgiven state is ultimately just as serious and dreadful as having already committed the unforgiveable sin. Seek ye the Lord while he may be found – return to our God, for he will abundantly pardon. Don’t let the fearful mystery surrounding the possibility of unforgiveable sin feed a scepticism about the riches of God’s mercy towards unworthy sinners, or bolster any sneaking unbelief about the availability of pardon for anyone whose heart’s desire is to be reconciled to God in Christ.
I’ll admit that this is not a topic I would voluntarily have picked to discuss. It is not an easy question, either in terms of simply understanding the scriptural teaching, or in terms of being able to consider in an appropriately reverent manner, because who can value the preciousness of a soul and the magnitude of the loss when forgiveness has not been found. “If thou, Lord, shouldest mark iniquities, O Lord, who shall stand? But there is forgiveness with thee, that thou mayest be feared … Let Israel hope in the Lord, for with the Lord there is mercy, and with him is plenteous redemption, and he shall redeem Israel from all his iniquities.”