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 .
Christian views on sin
Mortal sins are sins of grave (serious) matter, where the sinner performs the act with full knowledge and deliberate consent. (cf. CCC 1857)