SCRIPTURE COMMENTARY #236But the Pharisees hearing it, said: "This man casteth not out devils but by Beelzebub the prince of the devils." And Jesus knowing their thoughts, said to them: "Every kingdom divided against itself shall be made desolate: and every city or house divided against itself shall not stand. And if Satan cast out Satan, he is divided against himself: how then shall his kingdom stand? And if I by Beelzebub cast out devils, by whom do your children cast them out? Therefore they shall be your judges. But if I by the Spirit of God cast out devils, then is the kingdom of God come upon you. Or how can any one enter into the house of the strong, and rifle his goods, unless he first bind the strong? and then he will rifle his house. He that is not with me, is against me: and he that gathereth not with me, scattereth. Therefore I say to you: Every sin and blasphemy shall be forgiven men, but the blasphemy of the Spirit shall not be forgiven." (Matt. 12:24-31)
THE SIN AGAINST THE HOLY GHOST was committed by the Pharisees in this manner, that against the dictates of reason they ascribed our Lord's miracles to the power of the devil. They calumniated Him, saying that He was in league with the devil; whereas it was they who, by their persecution of Jesus, were serving the ends of Satan. Being full of the spirit of pride and envy, they refused to believe in our Lord's divine power. They willfully and obstinately resisted their reason, which, outwardly convinced by His stupendous miracles, and inwardly illuminated by the grace of the Holy Ghost, urged them to such a belief. Rather than recognize the truth that God was with our Lord, they had recourse to the most foolish evasions and lies. This willful resistance to God's grace hardened the Pharisees in obstinacy and impenitence, till finally it drove them to decide. They sinned against the Holy Ghost in a fourfold manner: they envied Jesus on account of His superior wisdom and power of working miracles; they resisted that which they knew to be true; they were obstinate in their opposition to our Lord; and they were hardened into a state of final impenitence.
[From 'A Practical Commentary on Holy Scripture' by Bishop Knecht, D.D.]
(1899 Douay-Rheims Bible)