And so I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven. Matthew 12:31
I remember talking to a Pastor as a kid many years ago about unforgivable sin. He actually told me not to worry about it. He said "If you're worried that you may have committed it, then that is all the evidence you need that you haven't committed it. Because anyone who commits it isn't worried about their salvation."
He went on to explain that it is impossible for a Christian to commit an unforgivable sin. Being a kid, I took him at his word. But today I find myself asking, "If it is impossible to commit the unforgivable sin, or if it is impossible to lose our salvation, then why does the Bible bother discussing it and warning us about it?"
Blasphemy against the Spirit is vague and mysterious enough for church leaders to explain away as of little consequence, not worth worrying about, etc. Usually, the response is something like "blasphemy against the Spirit is when an act of the Spirit is attributed to an act of Satan". By making the interpretation as literal as possible, the scope of possibilities for what else might be blasphemy against the Spirit is so much reduced as to be irrelevant. I'm not sure that's the best approach to such a serious subject. Shouldn't we take this seriously?
And even though Matthew 12:31 seems to imply that there is only one unforgivable sin, I would venture to say that there is at least one more:
But if you do not forgive men their sins, your Father will not forgive your sins. Matthew 6:15
And when you stand praying, if you hold anything against anyone, forgive him, so that your Father in heaven may forgive you your sins. [Some manuscripts sins. 26 But if you do not forgive, neither will your Father who is in heaven forgive your sins.] Mark 11:25-26
So we have a second unforgivable sin in the Bible, the sin of unforgiveness. The nature of unforgiveness is that it is ongoing. Unlike some sins which may be isolated one-time acts of disobedience (lieing, stealing, etc.), unforgiveness is a perpetual sin. If someone has wronged you and you have not yet forgiven them, then every passing moment that you continue in unforgiveness is another choice to sin... each second is a conscious decision to continue in unforgiveness. Therefore, unforgiveness fits the type and pattern of deliberate and continual sinfulness described in Hebrews:
If we deliberately keep on sinning after we have received the knowledge of the truth, no sacrifice for sins is left, but only a fearful expectation of judgment and of raging fire that will consume the enemies of God. Hebrews 10:26-27
Further, we see in the Lord's Prayer that Jesus taught us to ask God to forgive our debts, but only to the extent that we have forgiven others (Matthew 6:12). By implication, it seems that it would not be appropriate to ask or expect God to forgive us if we in turn have not forgiven others.
I think unforgiveness is the most poisonous condition a human can bring upon themselves. Nothing will destroy a person faster than bitterness and unforgiveness, both in this life and the next. The good news is that unforgiveness is quickly remedied by forgiveness. Once we choose to forgive, our previous unforgiveness becomes forgivable by God once more. The above scripture says that we should forgive "so that" God may forgive us. So unforgiveness is only unforgivable to the extent that we continue in it.
Are you struggling with unforgiveness? If so, I hope you have not "written off" the issue. I want to challenge you to take the matter of unforgiveness very seriously. Do whatever you must do, write someone, call them, go see them... if that's not possible, talk with a close friend about the situation, pray with them, be honest about where you're at... do whatever it takes so you can KNOW that you have truly forgiven those who have hurt you. It is literally a matter of life or death.