Synonyms for mortal sin

Why should the Roman Catholic Church call gluttony a mortal sin?

Think ye that one mortal sin will expiate other mortal sins?

No, if she was worshiped, it was enough; she was guilty of mortal sin.

According to her code and Tanqueray's she had sinned a mortal sin.

But the poor devil of a mercenary has no money, and this is the Mortal Sin.

Mortal sin, Jesuits wary of charging their penitents with, 555.

You have caused me to commit a mortal sin, in eating flesh on Friday.

To take ones life is to us a mortal sin; even that escape was denied me.

All concern and pleasure in the affairs of the world was mortal sin.

Must we love him as a godly man, who liveth in any great or mortal sin?