Eternal sin
In Catholic teaching there are six sins that blaspheme against the Holy Spirit. They are: Several passages in the Bible are frequently interpreted as referring to the unforgivable sin:
Great Apostasy
In Christianity, the term Great Apostasy is derived from the Second Epistle to the Thessalonians, in which the Apostle Paul informs the Christians of Thessalonica that a great apostasy must occur before the return of Christ, when "the Man of Sin is revealed, the Son of Destruction" (chapter ). As no such thing had yet occurred, Paul says that Christ cannot have returned yet.