Repeatedly I receive frantic inquiries from people fearful that they committed an unforgivable sin. It never seems to register that nowhere in the Bible are sins called "unforgivable." If a sin was unforgivable, then it means God refuses to offer forgiveness for certain sins. But that contradicts the nature of God. "For You, Lord, are good, and ready to forgive, and abundant in mercy to all those who call upon You" (Psalms 86:5). This desire to forgive is extended to all people. "The Lord is not slack concerning His promise, as some count slackness, but is longsuffering toward us, not willing that any should perish but that all should come to repentance" (II Peter 3:9). The claim that there are some sins God refuses to forgive contradicts the fact that God does not want anyone to perish.
The Roman Catholic Church classifies sins into two categories: venial and mortal. Venial sins are to be worked on but do not have to be confessed to a priest. Mortal sins must be confessed to a priest -- if not, the sin is considered deadly to a person's entrance into heaven. For a sin to be considered mortal it has to be a serious sin that was premeditated and willfully done. I suspect a lot of Catholics only half-listened to their denomination's teaching and, thus, quickly jump to the conclusion that serious sin is unforgivable, such as fornication or adultery. Or they might focus on whether they purposely did the sin -- knowing it was wrong but doing it anyway.
The Bible does not classify sins as the Roman Catholic Church does. All sins can lead to hell if the sin is not forgiven. "But the cowardly, unbelieving, abominable, murderers, sexually immoral, sorcerers, idolaters, and all liars shall have their part in the lake which burns with fire and brimstone, which is the second death" (Revelation 21:8). This list is an example of sins that lead to hell and is not meant to be taken as an exclusive list. Nor is it saying that doing one of these sins one time means a person is permanently condemned to hell. For example, Paul at one time was an unbeliever, but he became a believer in Christ and was saved from his sins. His past unbelief was not permanently held against him. Among the Christians in Corinth were people who were formally fornicators and adulterers, but they changed. "Do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived. Neither fornicators, nor idolaters, nor adulterers, nor homosexuals, nor sodomites, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners will inherit the kingdom of God. And such were some of you. But you were washed, but you were sanctified, but you were justified in the name of the Lord Jesus and by the Spirit of our God" (I Corinthians 6:9-10). Grave though these sins were, they were forgivable.
But what about sins that are willfully or purposely committed? Usually, Hebrews 10:26 is cited: "For if we go on sinning willfully after receiving the knowledge of the truth, there no longer remains a sacrifice for sins." I quoted this from the NASB because the King James and the New Kings James do not capture the tense of the verb as well as the NASB. The writer of Hebrews is not talking about a sin that was purposefully done once or a few times, but about a person who purposely continues in his sin. The warning is that the person cannot expect forgiveness in such a case. Thus, a person who lives with a sexual partner without marriage and claims that God won't hold it against them because they "love" each other is lying. No one can remain in sin and expect God to make allowances just for them. "Therefore consider the goodness and severity of God: on those who fell, severity; but toward you, goodness, if you continue in His goodness. Otherwise you also will be cut off" (Romans 11:22). As John points out, it is foolish to claim we have a relationship with the sinless God when we refuse to let go of our sins. "This is the message which we have heard from Him and declare to you, that God is light and in Him is no darkness at all. If we say that we have fellowship with Him, and walk in darkness, we lie and do not practice the truth. But if we walk in the light as He is in the light, we have fellowship with one another, and the blood of Jesus Christ His Son cleanses us from all sin" (I John 1:5-7).
Sins can be forgiven, even those which were willfully done at the moment of sin, if the sinner turns away from his sins and admits to God that he was wrong. "If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness. If we say that we have not sinned, we make Him a liar, and His word is not in us. My little children, these things I write to you, so that you may not sin. And if anyone sins, we have an Advocate with the Father, Jesus Christ the righteous" (I John 1:8-2:1).
But what if you became a Christian and then fell away? Isn't it impossible to come back to God? The passage under consideration is: "For it is impossible for those who were once enlightened, and have tasted the heavenly gift, and have become partakers of the Holy Spirit, and have tasted the good word of God and the powers of the age to come, if they fall away, to renew them again to repentance, since they crucify again for themselves the Son of God, and put Him to an open shame" (Hebrews 6:4-6). I have a question for you: Is this passage talking to the people who fell away or the faithful people who want to have them come back? It is written to the faithful people. The fallen way people are not being directly addressed. The writer is saying that when a formerly faithful Christian falls away into sin, it is impossible for me to convince them to come back because I have nothing to offer them that they have not already rejected. However, this passage does not rule out the possibility that the fallen brother might change his mind and come back.
But what about blasphemy? "Therefore I say to you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven men" (Matthew 12:31).
A part of the problem understanding what Jesus said is defining what blasphemy is. Many people imagine they have blasphemed when they had not. Blasphemy is actually an old word for slander. Blasphemy is when a person deliberately and purposely sets out to ruin the reputation of another person. The person knows what he is saying is false, but he doesn't care; he hates the other person so much that he will do or say anything to ruin him. "But the person who does anything defiantly, whether he is native or an alien, that one is blaspheming the LORD; and that person shall be cut off from among his people. Because he has despised the word of the LORD and has broken His commandment, that person shall be completely cut off; his guilt will be on him" (Numbers 15:30-31). Notice the elements included in blasphemy: slandering the Lord, defiant, despising what God has said, and breaking God's command.
A stray thought or a word said in anger without thought is not blasphemy. What the Pharisees did blasphemed Jesus. "Now when the Pharisees heard it they said, 'This fellow does not cast out demons except by Beelzebub, the ruler of the demons'" (Matthew 12:24). They took the miracle that Jesus did to accomplish good and deliberately recast it as a work of Satan. But what Jesus warned them was that it wasn't just him whom they were slandering. The Holy Spirit was the power behind the miracle, so they were inadvertently slandering the Father and the Spirit in their blasphemy of Jesus. If they continued on this path and deliberately slandered the Spirit because of their hatred of Jesus, there would be no way to rescue them. A person who willingly and purposely sets out to destroy the reputation of the Holy Spirit will be of such a mind that he has no desire to repent of his deed. Without a change of mind and a willingness to admit he is wrong, there can be no forgiveness. And because of his rejection of the Spirit, there are no words from God that can convince him that he is wrong.
Oddly, people who are fearful that they may have blasphemed the Holy Spirit are not guilty of that sin. Their very fear demonstrates they had not blasphemed the Spirit because a blasphemer would be defiant and proud that he slandered the Spirit, not scared.
Sadly, even explaining these points to some people does not satisfy them. I suspect some people want to believe that they are hopeless because eternal victim-hood gives them permission to never change. They spend their life in sorrow and may ultimately get what they claim to have. It isn't that they are unforgivable, but because they never repent God cannot give them the forgiveness He wants to offer them. "For godly sorrow produces repentance leading to salvation, not to be regretted; but the sorrow of the world produces death. For observe this very thing, that you sorrowed in a godly manner: What diligence it produced in you, what clearing of yourselves, what indignation, what fear, what vehement desire, what zeal, what vindication! In all things you proved yourselves to be clear in this matter" (II Corinthians 7:10-11). Don't let sorrow freeze you into inaction. Let your grief motivate you to leave sin and its sorrow behind.
"Therefore, since we have so great a cloud of witnesses surrounding us, let us also lay aside every encumbrance and the sin which so easily entangles us, and let us run with endurance the race that is set before us, fixing our eyes on Jesus, the author and perfecter of faith, who for the joy set before Him endured the cross, despising the shame, and has sat down at the right hand of the throne of God. For consider Him who has endured such hostility by sinners against Himself, so that you will not grow weary and lose heart" (Hebrews 12:1-3).