There's only one sin unto death, although there are many unpardonable sins. For instance, you may do something after you have become a Christian that is partly willful, and partly through failure to exercise the proper self-control that you might have exercised. To that extent it was your will that sinned; to that degree it was a willful sin; to that degree it was an unpardonable sin. And what would that mean? That would mean that you would need to receive some form of chastisement for that sin. It will not be pardoned. You can't say, "Lord, take it all away, please." It's all very proper to go to the Lord and ask him to forgive the sin. That is, to take away the feature of it that would come between you and the Lord and hinder you from enjoying his favor, but you must still expect that even if he restores you to the light of his countenance that there would be some stripes in proportion as there was any measure of willfulness connected with the sin. In that degree, you see, it is unpardonable, but is one that might be expiated in that degree. Now when I speak of expiation of sin I don't mean the original sin; the original is entirely expiated, and you can do nothing to get rid of it, but after you have gotten rid of original sin, and after you have become God's child, after you become a new creature, then you are on trial, and then in proportion as you may have willfulness, in that proportion you will have stripes; and so the Lord said, some will be beaten with many stripes, and some with fewer stripes, in proportion to their knowledge, etc. - Luke 12:47-48
There is a sin that is unto death. No amount of stripes will come in. No amount of stripes will be satisfactory. The individual committing that sin will die the second death. As the apostle says, "There is a sin unto death; I do not say that you shall pray for it." There would be no use to pray for it. The sin that is unto death is a willful sin, deliberate sin, intentional sin. The apostle describes this sin unto death in 6th and 10th chapters of Hebrews, and describes those who fall away, who renounce the Lord. Peter says, speaking of some of those, that they turned like the sow to wallowing in the mire, and like a dog to his vomit. Such a person, sinning willfully against light and knowledge, there is no more sacrifice for his sins; he has had his share of Christ's sacrifice and has misused it, and there is none remaining for him. There is a share in the sacrifice for Adam and all his children, every one of them, and they must all get their share; but whoever gets his share and then misuses it, there is nothing remaining, and his willfully turning away and counting the blood of the covenant wherewith he was sanctified a common thing, will mean his utter rejection by the Lord.
To my knowledge, you haven't rejected the Lord or what he's done for you by way of his death, he ransomed you. You my dear are like the prodigal son, who was welcomed back by his father. - Luke 15:11-32
And what exactly is the unpardonable sin and if you committ it why is your conscience seared ?