Eternal sin
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 unrepentant 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."
David Flusser
Flusser pursued his research at a time when many Jews blamed Christianity for Nazism. During his trial in Israel, the Gestapo officer Adolf Eichmann refused to take an oath on the New Testament, insisting he would swear only "in the name of God." Flusser commented in an editorial in the "Jerusalem Post": "I do not know who is the God in whose name Eichmann swore, but I am certain that it is neither the God of Israel nor the God of the Christian church. It should now become clear to the strongest Jewish opponents of Christianity that Christianity "per se" imposes limitations, and that the greatest crime against our people was not committed in the name of the Christian faith".