Proverbs 29:1 He, that being often reproved hardeneth his neck, shall suddenly be destroyed, and that without remedy.
[Patriarchs & Prophets pp 405] Notwithstanding they had had the most convincing evidence of God's displeasure at their course, in the destruction of the men who had deceived them, they dared to attribute His judgments to Satan, declaring that through the power of the evil one, Moses and Aaron had caused the death of good and holy men. It was this act that sealed their doom. They had committed the sin against the Holy Spirit, a sin by which man's heart is effectually hardened against the influence of divine grace.
“Whosoever speaketh a word against the Son of man,” said Christ, “it shall be forgiven him: but whosoever speaketh against the Holy Ghost, it shall not be forgiven him.” Matthew 12:32. These words were spoken by our Savior when the gracious works which He had performed through the power of God were attributed by the Jews to Beelzebub. It is through the agency of the Holy Spirit that God communicates with man; and those who deliberately reject this agency as satanic, have cut off the channel of communication between the soul and Heaven.
God works by the manifestation of His Spirit to reprove and convict the sinner; and if the Spirit's work is finally rejected, there is no more that God can do for the soul. The last resource of divine mercy has been employed. The transgressor has cut himself off from God, and sin has no remedy to cure itself. There is no reserved power by which God can work to convict and convert the sinner. “Let him alone” (Hosea 4:17) is the divine command. Then “there remaineth no more sacrifice for sins, but a certain fearful looking for of judgment and fiery indignation, which shall devour the adversaries.” Hebrews 10:26, 27.
Hebrews 6:4 For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost, 5 And have tasted the good word of God, and the powers of the world to come, 6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.
May The Lord add His blessing to the study of His word. God bless!