Matthew Henry Commentary Mark 3:22-30

"And the scribes that came down from Jerusalem said, He hath Beelzebub, and, By the prince of the demons casteth he out the demons. And he called them unto him, and said unto them in parables, How can Satan cast out Satan? And if a kingdom be divided against itself, that kingdom cannot stand. And if a house be divided against itself, that house will not be able to stand. And if Satan hath rise up against himself, and is divided, he cannot stand, but hath an end. But no one can enter into the house of the strong [man], and spoil his goods, except he first bind the strong [man]; and then he will spoil his house. Verily I say unto you, All their sins shall be forgiven unto the sons of men, and their blasphemies wherewith soever they shall blaspheme: but whosoever shall blaspheme against the Holy Spirit hath never forgiveness, but is guilty of an eternal sin: because they said, He hath an unclean spirit." — Mark 3:22-30 (ASV)

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 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 forgiveness for the greatest sins and sinners, a forgiveness purchased by Christ; 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.