Matthew 12:31

“Therefore I say to you, All sin and blasphemy will be forgiven to men, but the blasphemy against the Spirit will not be forgiven.”

Here Jesus directly challenges the Pharisees. So wonderful and so startling is the revelation of the power of the Spirit of God at work in the world, and therefore of the presence of the Kingly Rule of God, that to actually turn against it is to turn from God. And if the heart persists in such an attitude, it will become hardened. Then forgiveness will not be possible. Not because God withholds a forgiveness that is sought for, but because such men harden themselves against ever seeking it.

Jesus' words here are both an encouragement and a warning. They are an encouragement in that they declare that all kinds of sin and blasphemy may be forgiven man. There is nothing that puts us beyond God's forgiveness if we truly repent, if we acknowledge our sin and are changed in heart and mind in relation to it. They are thus an assurance that for all of us, however sinful we may have become, there is a way back to God.

But they are also a warning that there is one sin which will not be forgiven to any man, and that is to ‘blaspheme against the Holy Spirit'. In context this has in mind that the Spirit's work has been openly manifested before the Pharisees in such a way and in such an atmosphere of the presence of the Spirit of God, that it cannot be denied except by a perverse heart. Here the Spirit was openly and manifestly at work, and testifying to Jesus in every heart which was open to receive it. They could see it in what was happening all around them (as also had the towns of Chorazin, Bethsaida and Capernaum had seen it - Matthew 11:20). And of such things, when performed by what they saw as ‘good Jews', they had always spoken highly. So if they now closed their hearts to this work of the Spirit, and against all the evidence, because of their own obstinacy, imputed it to Satan, then they were closing their hearts to the only power that could save them. They were deliberately ‘calling good, evil' (Isaiah 5:20). But doing that involved the danger of establishing a permanent mindset. And once their hearts had become set in that way there would then be no way in which they could be saved. All hope of forgiveness would have gone. This would not be because God's forgiveness was not available. That is always available to those who seek it through Jesus. It would be because they would have set their own hearts against any chance of repentance. For every time we resist the working of the Holy Spirit, we add to the barrier in our own hearts against His working, until in the end we make it impossible for us even to think of repentance. True deathbed conversions are rare.

It should be noted in this regard that the sure sign that a person has not yet committed this sin is that they are troubled about it. For the person who has committed this sin will never be troubled about it. His heart will have become so unyielding that he no longer considers the matter any more. He is perfectly satisfied with his ways. But let the person who is troubled then make sure that he repents. For if he does not his opportunity may slip away, and may simply contribute towards his hardening.