... Nowhere does Jesus say that refusing to accept Him as our Savior is not a sin...
Where does Jesus say ANYTHING in the Bible about accepting Him as our Savior? Please provide a scripture reference for that.
All manner of sin and blasphemy can be forgiven, according to Matthew 12:31. This manner of sin is forgivable. Just because it is a sin does not make it unforgivable.
That means it is possible to be forgiven for rejecting Jesus Christ. When someone has been drawn to Christ by the Holy Spirit of God, resists and rejects that, they are guilty of sin. When that person repents for rejecting Jesus Christ, and resiting the drawing of the Holy Spirit, they may be saved from their sin. This is NOT the sin that Jesus Christ said was unforgivable.
Blasphemy is the open, verbal, speaking of words against God. When that is done against the Holy Spirit, that sin is unforgivable, and that is the subject of this thread. John Bunyan thought he had done this when he was young, and tempted by the devil to reject God. He said something in his heart that he was convinced was unforgivable. he had thought this, and may have even whispered this thought while alone. the very thing he said, concerning Christ, was, "Let Him go if He will."
John Bunyan spent a long time in spiritual agony because of this, and because he thought he had done what could not be forgiven - the very thing that we are being told is the unforgivable sin. He later understood better that the sin was not unforgivable, and he went on to become a great man of God. In his 60 years on this Earth, this formerly illiterate man wrote 60 of the best books in the English language.
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but the blasphemy against the Holy Ghost shall not be forgiven, not in this life, nor the life to come, according to Matthew 12:31.
He that speaketh a word against the Son of God can be forgiven, but he that speaketh against the Holy Ghost of God, can not be forgiven according to Matthew 12:32.
BLASPHEMY
http://dictionary.reference.com/browse/blasphemy
an act of cursing or reviling God
http://www.yourdictionary.com/blasphemy
The definition of blasphemy is saying something concerning God that is very disrespectful.
Something done in the heart is not necessarily changing the minds of other people around you. To speak words of this sort is to infect the people who hear with the vitriol from the heart of the person. It is speaking words that is the subject of this declaration by the LORD Jesus Christ recorded in Matthew 12.
James 3
5 Even so the tongue is a little member, and boasteth great things. Behold, how great a matter a little fire kindleth!
6 And the tongue is a fire, a world of iniquity: so is the tongue among our members, that it defileth the whole body, and setteth on fire the course of nature; and it is set on fire of hell.
7 For every kind of beasts, and of birds, and of serpents, and of things in the sea, is tamed, and hath been tamed of mankind:
8 But the tongue can no man tame; it is an unruly evil, full of deadly poison.
This is the manner of committing the sin that Jesus Christ stated would not be forgiven in this life nor in the life to come. It is speaking, with the tongue, words against the Holy Ghost. In the instance Jesus was addressing that brought this condemnation, it was attributing the works of the Holy Ghost to Beelzebub, the prince of the devils.