31 *Therefore I say to you: Every sin and blasphemy shall be forgiven men, but the blasphemy of the Spirit shall not be forgiven.
Of Spirit or against the Spirit and the Holy Ghost. St. Augustine takes notice, that this is one of the most difficult places in the Scriptures. According to the common exposition, here is not meant a sin committed by speaking against the third person of the blessed Trinity, the Holy Ghost, but that sin by which the obstinate Jews wilfully opposed Christ, and attributed those miracles to Beelzebub, which he performed by the Spirit of God, of which they could not be ignorant, but by a wilful blindness.
The sin here spoken of is that blasphemy, by which the Pharisees attributed the miracles of Christ, wrought by the Spirit of God, to Beelzebub, the prince of devils. Now this kind of sin is usually accompanied with so much obstinacy, and such wilful opposing the Spirit of God, and the known truth, that men who are guilty of it are seldom or ever converted; and therefore are never forgiven, because they will not repent. Otherwise there is no sin which God cannot, or will not forgive to such as sincerely repent, and have recourse to the keys of the Church.
Whosoever he be, says St. Augustine, that believeth not man's sins to be remitted in the Church of God, and therefore despiseth the bounteous mercies of God, in so mighty a work, if he continue in his obstinate mind till death, he is guilty of sin against the Holy Ghost. (Enchir. lxxxiii. ep. 50. in fine.)
32 And whosoever shall speak a word against the Son of man, it shall be forgiven him: but he that shall speak against the Holy Ghost, it shall not be forgiven him neither in this world, nor in the world to come.
It was their duty to have a knowledge of the Holy Ghost, and they obstinately refused to admit what was clear and manifest. Though they were ignorant of the divinity of Jesus Christ, and might take him to be merely the son of a poor artizan, they could not be ignorant that the expelling of demons, and miraculous healing of all diseases, were the works of the Holy Ghost. If, therefore, they refused to do penance for the insult offered to the Spirit of God, in the person of Christ, they could not hope to escape condign punishment. (St. Chrysostom, hom. xlii).
Against the Son of man, it shall be forgiven him; i.e. they who for want of sufficient instruction, were invincibly ignorant that Christ was God, might more easily be brought to the true knowledge and faith of Christ, and so receive forgiveness of their sins: but if he shall speak against the Holy Ghost, i.e. against the Spirit of God in Christ, and shall oppose the known truth, by attributing to the devil that doctrine, and those miracles, which evidently were from the Spirit and the hand of God, that sin shall never be forgiven him. But how is this consistent with the Catholic doctrine and belief, that there is no sin any man commits of which he may not obtain pardon in this life? To this I answer, that in what manner soever we expound this place, it is an undoubted point of Christian faith, that there is no sin which our merciful God is not ready to pardon; no sin, for the remission of which, God hath not left a power in his Church, as it is clearly proved by those words, Whose sins you shall forgive, they are forgiven them, &c. St. Chrysostom therefore expounds these words, shall not be forgiven them, to imply no more, than shall scarcely, or seldom be forgiven; that is, it is very hard for such sinners to return to God, by a true and sincere repentance and conversion; so that this sentence is like to that (Matthew xix. 26.) where Christ seems to call it an impossible thing for a rich man to be saved. In the same place St. Chrysostom tells us, that some of those who had blasphemed against the Holy Ghost, repented, and had their sins forgiven them. St. Augustine, by this blasphemy against the Spirit, understands the sin of final impenitence, by which an obstinate sinner refuseth to be converted, and therefore lives and dies hardened in his sins.