The articles on GotQuestions.org, which confused the person I was helping, said the only unforgivable sin is continued unbelief, to which he objected (in my paraphrase), "But if you 'believe' and have regret but not a transforming repentance, you've not been forgiven." His objection was well-founded, and I helped him come to a good combination of those two absolute statements by Jesus about the blasphemy of the Holy Spirit and Him never leaving us. I think Jesus' statement about the blasphemy of the Holy Spirit, more broadly interpreted, means people who see evidence of Him and reject that evidence are doomed, such as His contemporaries who weren't even attracted to the most obvious indications that God was working miracles through Him. Probably what He meant was that ongoing, unrelenting rejection of Him will never be forgiven. I helped the questioner past his worry that one intrusive thought of blasphemy will make God curse him. Some of my wording in this 5-part article is directly from what I wrote to him.
The Ryrie Study Bible
says about the Matthew 12 version of "blasphemy of the Holy Spirit":
Technically, according to the scribes, blasphemy involved direct and explicit abuse of the divine name. Jesus here teaches that it also may be the reviling of God by attributing the Spirit's work to Satan. The special circumstances involved in this blasphemy cannot be duplicated today; therefore, this sin cannot now be committed. Jesus exhorted the Pharisees to turn and be justified (vv. 33, 37).
The Bible Knowledge Commentary
says the same idea about Matthew 12, and about the Mark 3 parallel passage says:
It is one's preference for darkness even though he has been exposed to light (cf. John 3:19). Such a persistent attitude of willful unbelief can harden into a condition in which repentance and forgiveness, both mediated by God's Spirit, become impossible.
In its Luke 12 explanation, the B. K. Commentary
makes mention of Jesus' brothers later coming to faith (John 7:5, Acts 1:14).
I've heard there are miracles done by Christians in the Third World, like casting out evil spirits and healing. If people continue to persecute them in spite of the miracles, then they are "blaspheming the Holy Spirit," if that phrase is specifically about rejecting miraculous signs that should point to God. Sometimes they repent later on, like Saul of Tarsus, though he never saw proof that the early Christians were doing miracles until Jesus talked to him in a vision.
Mark 3 says in absolute wording that all sins and blasphemies shall be forgiven unless there's blasphemy against the Holy Spirit, because they were saying "He has an unclean spirit." Matthew 12 and Luke 12 convey the idea that blasphemy against Jesus is not as severe as blasphemy of the Holy Spirit, because the Holy Spirit and Father are how Jesus got His power. The distinction between blaspheming Jesus and blaspheming the Holy Spirit in those passages in the Gospels is not about whether God will or can (willingness vs. ability to forgive), but the two are combined (whatever God's willing, He's also able), and it's rhetorically pointing to a more severe kind of rejection, which is when people have undeniable evidence but don't want it. In John 15:24-25, He says, "If I had not done among them the works which no one else did, they would not have sin; but now they have both seen and hated Me and My Father as well. But they have done this to fulfill the word that is written in their Law, 'THEY HATED ME WITHOUT A CAUSE.'" (Actually, "Law" doesn't mean the Mosaic Law here, but their Hebrew Bible/Tanakh. "Hated me without a cause" is a motif in the Psalms.)
When I typed "Luke 10" into BibleGateway.com, misremembering which chapter has the verse about blasphemy of the Holy Spirit, I came upon Luke 10:16, which is an important part of this issue: "The one who listens to you listens to Me, and the one who rejects you rejects Me; and he who rejects Me rejects the One who sent Me." Remember how I mentioned the "keys of the kingdom" passage earlier, which the Catholic Church uses as justification for excommunication and papal authority. "The one who listens to you listens to Me" could be used by brash people to say "You didn't believe me when I shared the Gospel, so God's rejected you." People often don't go deep enough into the barriers to faith. Motivation by guilt about our sins doesn't work in all evangelism, though it is the primary means used in sermons and street evangelism. As for Jesus, He did miracles to prove His divine authority, but they pointed to His kind character. We are to be gracious
people to point to His character (see Part 5 of my "Good and Faithful Servant"
article for a discussion of what it means to be gracious). He didn't do miracles to scare people into submission, but to draw them to Himself.
This is why I have mixed feelings about some of the Old Testament stories where miracles' purpose, or at least result, is to frighten people into submission to God. Jesus explains the function of His miracles in John 5:36: "But the testimony which I have is greater than the testimony of John; for the works which the Father has given Me to accomplish — the very works that I do — testify about Me, that the Father has sent Me." In John 8:49-51, He gives His purpose statement: "I do not have a demon; but I honor My Father, and you dishonor Me. But I do not seek My glory; there is One who seeks and judges. Truly, truly, I say to you, if anyone keeps My word he will never see death." The purpose of it all is to free us from the curse of death, not to show off! When I discovered in the summer of 2014 the "Show me the Father" passage in John 14:7-9 (which you should definitely read in the context of the surrounding chapters), I saw that Jesus' disciples were wanting more supernatural powers like Adam and Eve and forgetting that these exist for the purpose of blessings others, so that when you bless others, it redounds to you in a deep way.
It sounds to me like the rhetoric in the "blasphemy of the Holy Spirit" statement is conveying the idea that His own name being blasphemed is unimportant, because they're not blaspheming Him, but "Him who sent Me" (the Father and Holy Spirit). They're blaspheming God, not just a man, when they blaspheme Jesus. Blaspheming Jesus is wrong, since He is innocent of any crimes, but that's a sin against a man, but when they do that in spite of the evidence He furnishes of His divine authority, they are committing a sin against heaven which will never be forgiven (unless they repent, I would add). The heaven and earth distinction in rhetoric was common in rabbinical style of Jesus' era, and is also part of the Book of Hebrews, Jesus' "If I showed you earthly things, and you didn't believe, how will you believe heavenly things?" (John 3:12), and 1 John's "How can he love God whom he has not seen if he doesn't love his brother whom he has seen?" (1 John 4:20).
The wording of Luke 12:8-10 provides me with an additional point:
And I say to you, everyone who confesses Me before men, the Son of Man will confess him also before the angels of God; but he who denies Me before men will be denied before the angels of God. And everyone who speaks a word against the Son of Man, it will be forgiven him; but he who blasphemes against the Holy Spirit, it will not be forgiven him.
If Jesus meant this literally rather than rhetorically, then those verses are self-contradictory, because Jesus said identifying with Him is how to find favor on Judgment Day, but then says blaspheming Him is an acceptable sin — if it's meant literally. This is rabbinical rhetoric. In the Book of Romans, Paul says that the existence of a written moral law raises the standard so that there is greater judgment. That's what Jesus is getting at in His statement about blasphemy of the Holy Spirit. "To whom much is given, much is required" (Luke 12:48) applies to anything in life, including our possessions meant for others' betterment and the truth we are given.
The two possibilities I see of how this "blasphemy of the Holy Spirit" issue could be interpreted are 1) Jesus is condemning them because they rejected "Him who sent Me" by rejecting the evidence, because He represents heaven and is not just a man of this earth or 2) He was saying people can get to a point of rejecting Him willfully, and being unredeemable, so that nothing
will ever change their minds. That happens to some people, I believe.
In parts 4-5, I will incorporate this into the issue of how people can change from self-centered, self-protective, and self-reliant, to being truly gracious.