Note: All Scripture quotations found in this article are from the text of the Authorized King James Version of the Bible.
One of the most asked questions about the Bible is the question, "What is the unpardonable sin?". This subject is talked about in Matthew 12:31-32 and Mark 3:29-30.
Matthew 12:31 "Wherefore I say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men. 32 And whosoever speaketh a word against the Son of man, it shall be forgiven him: but whosoever speaketh against the Holy Ghost, it shall not be forgiven him, neither in this world, neither in the world to come."
Some people say that this sin is the final rejection of Jesus Christ, which is wrong, nor is it cursing the Holy Spirit or saying a false healer today is possessed with the Devil. Remember that many of the Pharisees that rejected the Lord Jesus Christ in the four Gospels later got saved in the book of Acts (Acts 6:7, 15:5, 26:9). The blasphemy against the Holy Ghost is defined in Mark 3:29-30.
Mark 3:29 "But he that shall blaspheme against the Holy Ghost hath never forgiveness, but is in danger of eternal damnation: 30 Because they said, He hath an unclean spirit."
The blasphemy against the Holy Ghost that was not able to be forgiven was saying that Jesus Christ had an unclean spirit. That being the case, the "Unpardonable Sin" could only be committed when Jesus Christ was on the earth doing miracles. The only times in history that Jesus is on the earth was when He came to die on the Cross and when He comes back in the Millennium to reign as King for a thousand years. In conclusion, people in the Church Age do not have to worry about this sin because it is impossible to commit since Jesus is not present in the flesh(2 Cor. 5:16). The only sin that is not forgiven today is the sin of unbelief. If you die without trusting Jesus Christ alone, you have no second chances and will never be forgiven.
Hebrews 9:27 "And as it is appointed unto men once to die, but after this the judgment:"
John 14:6 "Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me."