Eternal sin

In Christian hamartiology, eternal sins, unforgivable sins, or unpardonable sins are sins which will not be forgiven by God. One eternal or unforgivable sin is specified in several passages of the synoptic gospels. Mark 3:28-29, Matthew 12:31-32, and Luke 12:10 state that there is one sin considered eternal and that is "blasphemy against the Holy Spirit".

Several passages in the Bible are frequently interpreted as referring to the unforgivable sin:

According to the Catechism of the Catholic Church §1864, there are no limits to the mercy of God, but anyone who deliberately refuses to accept his mercy by repenting, rejects the forgiveness of his sins and the salvation offered by the Holy Spirit. Such hardness of heart can lead to final impenitence and eternal loss.

Thomas Aquinas lists, or has responded to six sins that supposedly go against the Holy Spirit:

Thomas Aquinas explains that the unforgivability of blasphemy against the Holy Spirit means that it removes the entrance to these means of salvation—however, it cannot hinder God to take away this obstacle by way of a miracle.

According to one source however these are mortal sins against the Holy Spirit and not blasphemy against him though apart from presumption none of these are listed as mortal sins by the Catechism.

However, the Church further believes there is no offence, however serious, that cannot be taken away by Baptism, or absolved from in the Confessional—that no one, however wicked and guilty, may not confidently hope for forgiveness. The Catechism says that Christ desires "the gates of forgiveness should always be open to anyone who turns away from sin." As did St Augustine the Catholic Church today teaches that only dying not being sorry for one's sins is the only unforgivable sin. Indeed, in Dominum et vivificantem Pope John Paul II writes "According to such an exegesis, 'blasphemy' does not properly consist in offending against the Holy Spirit in words; it consists rather in the refusal to accept the salvation which God offers to man through the Holy Spirit, working through the power of the Cross", and "If Jesus says that blasphemy against the Holy Spirit cannot be forgiven either in this life or in the next, it is because this 'non-forgiveness' is linked, as to its cause, to 'non-repentance,' in other words to the radical refusal to be converted. This means the refusal to come to the sources of Redemption, which nevertheless remain 'always' open in the economy of salvation in which the mission of the Holy Spirit is accomplished."

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