Eternal sin
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 in taking away this obstacle by way of a miracle.
Christianity and Judaism
Hebrew has several words for sin, each with its own specific meaning. The word "pesha", or "trespass", means a sin done out of rebelliousness. The word "aveira" means "transgression". And the word "avone", or "iniquity", means a sin done out of moral failing. The word most commonly translated simply as "sin", "het", literally means "to go astray". Just as Jewish law, "halakha" provides the proper "way" (or path) to live, sin involves straying from that path. Judaism teaches that humans are born with free will, and morally neutral, with both a "yetzer hatov", (literally, "the good inclination", in some views, a tendency towards goodness, in others, a tendency towards having a productive life and a tendency to be concerned with others) and a "yetzer hara", (literally "the evil inclination", in some views, a tendency towards evil, and in others, a tendency towards base or animal behavior and a tendency to be selfish). In Judaism all human beings are believed to have free will and can choose the path in life that they will take. It does not teach that choosing good is impossible—only at times more difficult. There is almost always a "way back" if a person wills it. (Although texts mention certain categories for whom the way back will be exceedingly hard, such as the slanderer, the habitual gossip, and the malicious person)