Those of you participating in the 90 Day New Testament Reading Plan recently came across a potentially disturbing passage in Mark in which Jesus says:
28 “I assure you that human beings will be forgiven for everything, for all sins and insults of every kind. 29But whoever insults the Holy Spirit will never be forgiven. That person is guilty of a sin with consequences that last forever.” 30He said this because the legal experts were saying, “He’s possessed by an evil spirit.” — Mark 3:28-30 (Common English Bible)
“Insults” is traditionally translated “blasphemes.” But no matter how the passage is translated, it and parallels in Matthew and Luke have terrified pious, conscientious Christians for centuries. As John Wesley put it:
How immense is the number in every nation throughout the Christian world of those who have been more or less distressed on account of this Scripture! — John Wesley, Sermon 86, “A Call to Backsliders.”
I don’t consider myself particularly pious and conscientious, but for a long time, I was one of those “distressed on account of this Scripture.” The best explanation I’ve found came from Lamar Williamson, Jr. Here is his explanation, with my additions for clarification in brackets:
The intention of this text [Mark 3:28-30] is not primarily to define the unpardonable sin and even less is it to equip us to decide who has committed it. Jesus himself does not state that his adversaries had done so, according to Mark, though he warns them in the most serious terms. Mark 3:30 (not found in the parallels [in the other gospels]) does, however, offer a particular understanding of the unpardonable sin. The sin is to recognize [by the working of the Holy Spirit in the individual] a supernatural power at work in Jesus and yet to call that power unclean or evil. The sin is unforgivable because it rejects the very agent of God’s healing and forgiveness (see [Mark] 2:17 and 10:45). The imperfect tense of the verb in verse 30 is significant: “… because they were saying, ‘He has an unclean spirit.’ ” This indication of repeated or habitual action, unfortunately obscured in the RSV [the Revised Standard Version, the translation Williamson was referencing], suggests a fixed position, a firm decision, and not simply skepticism. The doubt of honest inquirers is always honored in Mark. What places one in mortal danger is considered, deliberate rejection of the God at work in and through Jesus. The text continues to function as a warning to all readers of the seriousness of our response to the One who confronts us here.
Those readers who not only define the unpardonable sin, but believe that they have committed it, should observe, first, that the very fact of their concern means they are not guilty of the deliberate, obstinate rejection of God’s Holy Spirit which alone is unforgivable. Only those who set themselves against forgiveness are excluded from it. — Lamar Williamson, Jr., Mark: Interpretation: A Bible Commentary for Teaching and Preaching.
The above is the most comprehensive explanation of the blaspheme against the Holy Spirit that I’ve come across.