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 (blasphemy against the Holy Spirit) is specified in several passages of the Synoptic Gospels, including , , and .
Adam
Christianity sees human nature as irrevocably stained by the sin of Adam. The idea is not found in Judaism (nor in Islam), and was introduced by the Apostle Paul, drawing on currents in Hellenistic Jewish thought which held that Adam's sin had introduced death and sin into the world. Sin, for Paul, was a power to which all humans are subject, but Christ's coming held out the means by which the righteous would be restored to the Paradise from which Adam's sin had banished mankind. He did not conceive of this original sin of Adam as being biologically transmitted or that later generations were to be punished for the deeds of a remote ancestor. It was Saint Augustine who took this step, locating sin itself in male semen: when Adam and Eve ate of the fruit they were ashamed and covered their genitals, identifying the place from which the first sin was passed on to all succeeding generations. Only Jesus Christ, who was not conceived by human semen, was free of the stain passed down from Adam. (Augustine's idea was based on the ancient world's ideas on biology, according to which male sperm contained the entire unborn baby, the mother's womb being no more than a nurturing chamber in which it grew.)