As a Professional Counselor and Subliminal360 an active Christian, I have often met clients who come to me ashen faced and trembling because they have believed that they have committed the unpardonable sin. That is, Blasphemy of the Holy Spirit. I talk to them from my own experience of which I have recorded in a book for those folk to find for themselves that such an offense can only be committed when you die. There are many recorded people in the past who have died cursing Jesus Christ and His Sacrifice.
That my dear friends is the unforgivable sin. You have died breathing your last breath cursing the only redeeming name that can ever save your soul. Jesus. Upon death, you can't turn around and ask for forgiveness because your will and your breath have gone, long gone.God is a loving God. He is always willing to hear a repentant heart.
Many a cursing man or woman has received forgiveness at the Cross simply by acknowledging their sin and allowing God to forgive and let them move on in life. Many wonderful Hymns have been written from that craggy place on their knees speaking of that 'once I was blind and now I see' place.of such hymn writers as John Newton and his wonderful hymn " Amazing Grace".