I recently acquired a volume of Northrop Frye’s collected works (vol. 5 of the “Late Notebooks”: Architecture of the Spiritual World). Random, I know.
One of the entries addresses Mark 3:29 (“whoever blasphemes against the Holy Spirit never has forgiveness, but is guilty of an eternal sin”). Here is what Frye has to say:
 I regret very much that the gospel reports Christ as saying that the sin against the Holy Spirit is unforgivable … The sin against the Holy Spirit is original sin itself. Perhaps it can’t be “forgiven,” but it must be annihilated, or the whole Christian structure, which depends on a love that forgives everything, is a lot of balls. That’s what I think now, anyway. An unpardonable sin means a stinker God, and I will never accept such a creature in the Christian set-up.
More to follow, I’m sure.