The Unpardonable Sin

Here's Iain Campbell, discussing John Bunyan and one of Bunyan's characters in Pilgrim's Progress:

So here is a man, portrayed as being in a condition where he knows that he has committed unpardonable offences against God, and finds himself now shut out of the promises. There is no doubt that the Bible portrays such a condition, but does it teach that it is possible for someone to know that he is past grace and beyond repentance? This man says that he was once 'a fair and flourishing professor' (p34), that is, one who professed faith, and he lists his sins as follows:

I left off to watch and be sober; I laid the reins upon the neck of my lusts; I sinned against the light of the Word, and the goodness of God; I have grieved the Spirit, and he is gone; I tempted the devil, and he is come to me; I have provoked God to anger, and he has left me; I have so hardened my heart, that I cannot repent. (p34)

When Interpreter asks, 'is there no hope but you must be kept in the iron cage of despair?', the man replies, 'no, none at all'.

The question is not whether it is possible for a person to be in this situation, but whether it is possible for him to be in it and be conscious of it. On the one hand, Bunyan himself was plagued with the thought that he had committed the unpardonable sin, by which he says that 'the word of the gospel was forced from my soul, so that no promise or encouragement was to be found in the Bible for me ... I saw there was cause for rejoicing for those who held on to Jesus; but as for me, I had cut myself off by my transgressions and left myself no place where either my foot or my hand could lay a firm hold among all the support and props in the precious Word of life' (Grace Abounding, p102).

But these were the fears of someone struggling to find hope; and I have always taken it as a rule of thumb that if anyone is afraid that they have committed the unpardonable sin, that is a sure sign that they haven't. It seems that part of the hardness of those who have committed it is not to be concerned about it one way or the other. This is how the upardonable sin is dealt with in most evangelical theologies:

The fact that the upardonable sin involves such extreme hardness of heart and lack of repentance indicates that those who fear they committed it, yet still have sorrow for sin in their heart and desire to seek after God certainly do not fall in the category of those who are guilty of it. Berkhof says that 'we may be reasonably sure that those who fear that they have committed it and worry about this, and desire the prayers of others for them, have not committed it' (Wayne Grudem, Systematic Theology, p509, quoting Berkhof, p253)