Augustine of Hippo, on Matt 12:31

“Therefore I say to you: Every sin and blasphemy shall be forgiven men, but the blasphemy of the Spirit shall not be forgiven.”

“(ubi sup.) But if this were said in such manner, then every other kind of blasphemy is omitted, and that only which is spoken against the Son of Man, as when He is pronounced to be mere man, is to be forgiven. That then that is said, All manner of sin and blasphemy shall be forgiven unto men, without doubt blasphemy spoken against the Father is included in its largeness; though here again that alone is declared irremissible which is spoken against the Holy Ghost. What then, hath the Father also taken upon Him the form of a servant, that the Holy Ghost is thus as it were spoken of as greater? For who could not be convicted of having spoken a word against the Holy Spirit, before He become a Christian or a Catholic? First, the Pagans themselves when they say that Christ wrought miracles by magic arts, are they not like those who said that He cast out dæmons by the Prince of the dæmons? Likewise the Jews and all such heretics as confess the Holy Spirit, but deny that He is in the body of Christ, which is the Church Catholic, are like the Pharisees, who denied that the Holy Spirit was in Christ. Some heretics even contend that the Holy Spirit Himself is either a creature, as the Arians, Eunomians, and Macedonians, or deny Him at least in such sort that they may deny the Trinity in the Godhead; others assert that the Father alone is God, and the same is sometimes spoken of as the Son, sometimes as the Holy Spirit, as the Sabellians. The Photinians also say, that the Father only is God, and that the Son is nothing more than a man, and deny altogether that there is any third Person, the Holy Spirit. It is clear then that the Holy Spirit is blasphemed, both by Pagans, Jews, and heretics. Are all such then to be left out, and looked upon as having no hope? For if the word they have spoken against the Holy Spirit is not forgiven them, then in vain is the promise made to them, that in Baptism or in the Church, they should receive the forgiveness of their sins. For it is not said, ‘It shall not be forgiven him in Baptism;’ but, Neither in this world, nor in the world to come; and so they alone are to be supposed clear of the guilt of this most heavy sin who have been Catholics from their infancy. Some again think that they only sin against the Holy Ghost, who having been washed in the laver of regeneration in the Church, do afterwards, as though ungrateful for such a gift of the Saviour, plunge themselves into some deadly sin, such as adultery, murder, or quitting the Christian name, or the Church Catholic. But whence this meaning can be proved, I know not; since place for penitence of sins however great was never denied in the Church, and even heretics are exhorted to embrace it by the Apostle. If God peradventure will give them repentance to the acknowledging of the truth. (2 Tim. 2:25.) Lastly, the Lord says not, ‘If any Catholic believer,’ but, Whoso shall speak a word, that is, whosoever, it shall not be forgiven him neither in this world, nor in the world to come.”

Imported from an open dataset — not yet checked against the printed edition.