Q: If the unpardonable sin is the one that grieves the Holy Spirit, my question is why does it not also grieve the FATHER and the SON? Why just the Holy Spirit?
A: This is a question that has been alluded to in the past. It seems confusing to most people. To answer your question up front, the Father and the Son are just as grieved over the sin of the blasphemy of the Holy Spirit as the Holy Spirit is. The person of the Holy Spirit serves as the presence of God in our midst.
It is important to understand that the real issue does not rest with the Holy Spirit simply being grieved that ends in the unpardonable sin, but it actually goes deeper. Ephesians 4:30 states, “And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption.”
There are also other scriptures to consider, Isaiah 63:10, “But they rebelled, and vexed his holy Spirit; therefore he was turned to be their enemy, and fought against them,” as well as 1 Thessalonians 5:19, “Quench not the Spirit,” Acts 5:9, “…ye have agreed together to tempt the Spirit of the Lord,” 1 Samuel 16:14, “But the Spirit of the LORD departed from Saul, and an evil spirit from the LORD troubled him.”
It is clear that when rebellion is present, the Holy Spirit is vexed, when a wrong spirit is present the Holy Spirit will be quenched in His work, and wherever there is perversion He will be grieved, while if someone tempts Him it could easily result in judgment, and any disobedience while rejecting righteousness will result in Him withdrawing His presence and departing. This brings us to what causes the final offense against the Holy Spirit, that of blasphemy, the unpardonable sin.
Matthew 12:25-32 gives us this insight into the sin of blasphemy. Blasphemy means to vilify, rail and speak evil against. When you read the Scripture references in Matthew, blasphemy comes down to accrediting the works of the Holy Spirit as being Satan’s wicked deeds which is a type of vilification of the Holy Spirit, or accrediting Satan with the work of the Holy Spirit which is to speak evil against that which is holy. The reason this becomes the unpardonable sin is because the person and work of the Holy Spirit must be properly discerned to receive the gifts and promises of God. The Father will draw people to the Son, and the Son will invite people to partake of the Living Water (Holy Spirit) to receive eternal life, but the Spirit alone is the one who convicts people of sin to point them to the salvation of Christ, as well as becoming the motivating power behind repentance that leads to one being born again. He seals a saved person to redemption, leads one into all truth, and ultimately sanctifies the believer by setting him or her apart for the work of God (John 3:3, 5; 4:14; 5:37-39; 6:44; 16:7-13; 1 Corinthians 2:9-14; Ephesians 1:11-14; 1 Peter 1:2, 22-23).
When it comes to salvation, the Father sent the Son and the Son gave His life, but it is the Spirit who is working in this present world to bring revelation of salvation to a person’s spirit. If a person rejects the work of the Holy Spirit, there is nothing left that can bring conviction of sin, righteousness, or judgment. If a person accredits the work of the Holy Spirit to Satan, then the Spirit is stripped of the power to do His work in a person due to unbelief. If a person fails to discern Satan and accredits and receives his presence and works as belonging to the Holy Spirit, than there is no means to properly discern, and the Spirit is robbed of His authority to bring forth unadulterated truths, corrections, and revelation.
As you can see when the Spirit is grieved so are the Father and Son, but when the Holy Spirit’s work is rejected or is accredited to Satan, all that remains is judgment. It is for this reason people need to know the Person of the Holy Spirit, be able to properly discern His Work, and by faith walk according to His leading.
I hope this answers your question.