Verse 28. - All their sins shall be forgiven unto the sons of men, etc. St. Mark adds the words (ver. 30), "Because they said, [ἔλεγον, 'they were saying,'] He hath an unclean spirit." This helps us much to the true meaning of this declaration. Our Lord does not here speak of every sin against the Holy Spirit, but of blasphemy against the Holy Spirit. These words of St. Mark point to a sin of the tongue mere especially, although not excluding thoughts and deeds against the Holy Spirit. Observe what these scribes and Pharisees did; they cavilled at works manifestly Divine - works wrought by God for the salvation of men, by which he confirmed his faith and truth. Now, when they spake against these, and knowingly and of malice ascribed them to the evil spirit, then they blasphemed against the Holy Ghost, dishonoring God by assigning his power to Satan. What could be more hateful than this? What greater blasphemy could be imagined? And surely they must be guilty of this sin who ascribe the fruits and actions of the Holy Spirit to an impure and unholy source, and so strive to mar his work and to hinder his influence in the hearts of men.

3:22-30 It was plain that the doctrine of Christ had a direct tendency to break the devil's power; and it was as plain, that casting of him out of the bodies of people, confirmed that doctrine; therefore Satan could not support such a design. Christ gave an awful warning against speaking such dangerous words. It is true the gospel promises, because Christ has purchased, forgiveness for the greatest sins and sinners; but by this sin, they would oppose the gifts of the Holy Ghost after Christ's ascension. Such is the enmity of the heart, that unconverted men pretend believers are doing Satan's work, when sinners are brought to repentance and newness of life.Verily I say unto you,.... The Scribes and Pharisees, who had not only blasphemed him, but the Spirit of God also:

all sins shall be forgiven unto the sons of men, and blasphemies wherewith soever they shall blaspheme; God; or the Son of God, angels, and men, and that through the blood of Christ, and when brought to a sense of the evil of them; for though pardon is procured before, it is not applied till then; See Gill on Matthew 12:31.