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."
Caelestius
Caelestius also went much further than Pelagius in stating that the sin of Adam, as chronicled in the Biblical Book of Genesis had only harmed himself, and not all of humanity, as Augustine had taught in his writings and sermons (Pelagius has been accused of starting this teaching, but in fact he anathematized the opinions of Caelestius at the Synod of Lydda in 415 A.D., as well as in a letter to the pope shortly thereafter). In several books on the topic, Augustine also argued that Pelagius and Caelestius neglected to take God's divine grace into account. Augustine believed Adam's sin ("Fall") in the Garden of Eden had caused human beings to lose the ability to not sin. (""non posse non peccare"" in Latin) and therefore, all good deeds done by Christians come from them being enabled by God to do good. In contrast, Pelagius believed that God gave the power of free will to all men, not just Christians, in such a way that no one was forced into sin (Augustine even wrote certain remarks that seemed to imply that any such forced action would not in fact be sinful). Caelestius again appears to have gone beyond this and denied that Christian goodness is due to grace, on the grounds that this would imply that if any Christian sinned, it was because God's grace had failed; once again at the Synod of Lydda Pelagius anathematized this position (although he stated that he did not mean to indicate whether they were Caelestius' opinions or not).