What is the Unpardonable sin?
The “unpardonable sin” is just an expression and does not appear in the Bible. However, the idea is based on certain passages like Matthew 12:31, where Christ teaches that “blasphemy against the Spirit will not be forgiven men.” This assertion was made in response to a statement by certain Pharisees who, after witnessing one of Jesus’ healings, said that He cast out demons through the power of Beelzebub, the ruler of the demons (Matthew 12:22–24; Mark 3:22–30).
The Holy Spirit impresses truth upon our mind and heart, and convicts us of sin (John 14:17; 16:13). In Numbers 14:18, Moses quotes God as saying that He is “longsuffering and abundant in mercy.” 2 Peter 3:9 confirms that God is longsuffering and adds that He is “not willing that any should perish but that all should come to repentance.”
However, His Spirit will not continue to strive indefinitely with the hard, stubborn heart (Genesis 6:3). When the promptings of the Holy Spirit are persistently resisted and refused, that person is left in darkness. Paul alluded to this when he said that God would allow people to continue to believe lies based on their rejection of the truth (2 Thessalonians 2:10–11).
Does that mean that person can never be saved into God’s Kingdom? Absolutely not. The words of 1 John 1:9 tell us, “If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness.”
In conclusion, blasphemy of the Holy Spirit is to continually reject truth so that one never surrenders fully to the Holy Spirit’s guidance.
How can a person know if he has committed the unpardonable sin? There is a simple and easy answer: Anyone who is still being convicted of sin and feels a drawing to God has not yet grieved away the Holy Spirit.