Most people will say that there is NO sin that can not be forgiven. That is a lie. Some churches will actually tell a person that divorce is the unforgivable sin. That is a lie! Most churches will not even teach this, which can be dangerous. This is why the rapture doctrine is so harmful because it publicly covers the elect's mission on this earth during the end times. We have a mission! If you are a part of the elect and you have not been taught, you may commit the unpardonable sin without even knowing it! I am here to teach you, beloved.
Mark 3:28-29 “Verily I say unto you, All sins shall be forgiven unto the sons of men, and blasphemies wherewith soever they shall blaspheme: But he that shall blaspheme against the Holy Ghost hath never forgiveness, but is in danger of eternal damnation.”
Luke 12:10-12 “And whosoever shall speak a word against the Son of man, it shall be forgiven him: but unto him that blasphemeth against the Holy Ghost it shall not be forgiven. And when they bring you unto the synagogues, and unto magistrates, and powers, take ye no thought how or what thing ye shall answer, or what ye shall say: For the Holy Ghost shall teach you in the same hour what ye ought to say.”
The above are directly from Jesus Christ Himself, backed up by multiple witnesses and logged in the Holy Bible. Now, this sin can only be committed by the elect in the end of days when they are delivered up before Satan. You can read of it in Matthew 24, Mark 13, Luke 12 and Luke 21.
Further Reading:
Luke 12:1-12
Mark 13
A popular question that is asked is whether or not non-believers will be saved once they see for themselves that God is real. God is fair. He makes sure that everyone gets a chance to choose a side. In some case where a non believer is one purely because they were never taught about God, scripture confirms that God is compassionate and they will have the opportunity to be taught and choose a side. But for those who have heard in their lifetime, have been taught or have been otherwise informed of God being our divine Creator and Jesus being the Son of God by which the price for salvation has been paid, and they choose to mock, forsake and deny Christ/our Father, they have chosen to have their soul be put to death. They don't get a second chance- when you learn, you choose. Good scriptures to read more about this are: Ezekiel 18, Matthew 10 and 2Timothy 2.
Please remember the reason for the season. While December 25th is widely celebrated as the birth of Christ, when it was actually the conception whereby the Holy Spirit began dwelling with us as a babe in the womb, we should not lose sight of the greatest gift ever given to this world. Jesus Christ is our salvation, He paid the price. No one gets to the Father but through Him.