Jesus Himself said in Matthew 12:31, “Therefore, I say to you, every sin and blasphemy will be forgiven people, but blasphemy against the Spirit will not be forgiven.” Blasphemy against the Holy Spirit is any sin that a person clings to by continually resisting the convicting power of the Holy Spirit. The unforgivable, it is any sin that a person doesn’t want to give up, confess, or even ask forgiveness for and additionally doesn’t want to hear any more about it from the Holy Spirit.
Any sin mankind wants pardon for is forgivable, however, if we turn our backs on the voice of the Holy Spirit we begin to silence His convictions and eventually we cannot hear His convicting power. This effectively blocks the working of God in our lives because we have reached a point where we cannot respond to the promptings of the Holy Spirit.
If a person still desires forgiveness and confesses his sins, those sins will be forgiven. Do you hear the Holy Spirit calling you to remove some walls in your life so that Jesus can freely communicate and spend time with you? Why not follow the promptings of the Holy Spirit right now and ask for help breaking down any wall of separation between you and God.
There is no Biblical support for a believer committing this sin. If you are worried that you may have committed the sin and can’t be forgiven, then don’t be concerned. If you had, you wouldn’t be concerned.