Mark 3:28-30, “Truly I tell you, the sons of men will be forgiven all sins and blasphemies, as many as they utter. 29But whoever blasphemes against the Holy Spirit will never be forgiven; he is guilty of eternal sin”. 30Jesus made this statement because they were claiming, “He has an unclean spirit.”
Matthew 12:29 informs us that it was “the Spirit of God” in Jesus who cast out demons:
"But if I cast out demons by the Spirit of God, then the kingdom of God has come upon you.”
But John 14:10 informs us that the Holy Spirit is “the Spirit of the Father” who was “in him” (in Christ Jesus):
Jesus said in John 14:10 (BLB), “…the Father dwelling in Me does His works.”
Jesus had indicated that the Spirit of the Father was in him and was doing the mighty works through him (John 14:10 BLB “…the Father dwelling in Me does His works”). Since Matthew 12:28 proves that it was “the Spirit of God” who did the mighty works through Jesus, the Holy Spirit must be the Spirit of the Father who dwelt in Jesus and did the mighty works through him. In like manner, Acts 1:2 (NIV) states that Jesus “… had given commands through the Holy Spirit” to his “apostles whom he had chosen”. But John 12:49 (ISV) states that “the Father” Himself had given Jesus the commandments to speak, “I haven't spoken on my own authority. Instead, the Father who sent me has himself commanded me what to say and how to speak”. Hence, the Spirit who was in Christ Jesus (while Jesus dwelt on the earth as a man) was the Holy Spirit of the Father who gave Jesus the commands to give to his apostles. This is that Divine Holy Spirit who was in Christ Jesus who did the works through him in which Jesus claimed his divine identity (John 8:58 – “…before Abraham was I AM”; John 10:37-39 – “If I am not doing the works of My Father, then do not believe Me. 38But if I am doing them, even though you do not believe Me, believe the works themselves, so that you may know and understand that the Father is in Me, and I in the Father.” 39At this, they tried again to seize Him, but He escaped their grasp.…; John 14:10 (KJV) – “the Father abiding in me, He does the works”).
Jesus said in John 12:37-38, “If I am not doing the works of My Father, then do not believe Me. 38But if I am doing them, even though you do not believe Me, believe the works themselves, so that you may know and understand that the Father is in Me, and I in the Father.”
Since Jesus claimed to do the works of his Father, we know that it was the Father working in and through the Son rather than an alleged third God the Holy Spirit doing so. Therefore the scriptures prove that the Holy Spirit is the Spirit of the Father who dwelt in Jesus to do the mighty works (Matthew 12:28) and to give him the words and commandment to speak (John 12:49; Acts 1:2).
A sincere Trinitarian asked, “Why does Jesus say in Matthew 12:31 (NASB), ‘31 And so I tell you, every kind of sin and slander can be forgiven, but blasphemy against the Spirit will not be forgiven. 32 Anyone who speaks a word against the Son of Man will be forgiven, but anyone who speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come’?”
He continued, “If the Father is Jesus, and Jesus is now the Holy Spirit, why does He make this clear distinction between Himself and the Spirit? The only reason why I ask that is because if your position is biblical, this passage doesn't make any sense to me”.
MY RESPONSE: John 5:26 clearly points to a post incarnational distinction between the Father who is the Holy Spirit outside of the incarnation and the Son who is the full incarnation of the Holy Spirit of the Father who became a true man inside of the incarnation through the virgin. For John 5:26 clearly proves that the human life of the Son was granted as a distinct human life just as the Father has a distinct divine life in himself (John 5:26 BSB, “For as the Father has life in Himself, so also He has granted the Son to have life in Himself”). Hence, men can blaspheme "the man Christ Jesus" (the distinct human life) but not the immutable Spirit of the Father (the distinct non-human life of the Spirit of the Father in the heavens) who did the mighty works through the man (the Son - John 14:10). Therefore, the human child born and son given can be mocked and blasphemed by men while being forgiven, but not the blaspheming against the Holy Spirit of the Father who did those mighty works through His Son.
True Oneness Theology does not ignore the distinction between the Father who remained “the same (Heb. 13:8; Mal. 3:6)” unchangeable omnipresent Spirit and the Son who is the Spirit of the Father who was “reproduced” or “copied” from that Eternal Spirit to become a true man (see Heb. 1:3 – “character” [copy, reproduction] and "hypostasis" [Substance or Essence of Being]). For just as Hebrews 1:3 informs us that the Holy Spirit of the Father who descended on the virgin (Luke 1:35) also became the “reproduced” “copy” of the Father’s “substance of Being (Heb. 1:3)” as “the man Christ Jesus (1 Tim. 2:5; Heb. 2:17),” so “icon” in Col. 1:15 (Jesus is “…the image [“icon”] of the invisible God”) points to the same thing as “character” in Hebrews 1:3. Wherefore, “the man Christ Jesus” as the human “child born” and “son given” (Isaiah 9:6) is “the image” or “copy” (Heb. 1:3) of the invisible Spirit of “the Mighty God” and “Everlasting Father (Isaiah 9:6)” as a true human son, because the son of God is “God with us (Matthew 1:23)” as a true man who was “made fully human in every way (Heb. 2:17 NIV) via his virgin conception.
In conclusion, men can blaspheme “the man Christ Jesus” and be forgiven because Jesus is the distinct human life called the son (John 5:26 “…as the Father has life in himself, so he has granted the Son life in himself”) who is the copied image of the Invisible Father (Col. 1:15; Heb. 1:3). In contradistinction, men cannot blaspheme the immutable Holy Spirit of the Father (the distinct non-human life of the Spirit of the Father in the heavens – John 5:26) who did the mighty works through the man Christ Jesus (through the distinct human son - John 14:10). Hence, men cannot blaspheme the Father who is the Holy Spirit without being guilty of the unpardonable sin. Therefore, the human child born and son given can be mocked and blasphemed by men while being forgiven, but not the blaspheming against the Holy Spirit of the Father who did those mighty works through His distinct human son.