wrath vs mortal sin

wrath and mortal sin both are nouns.

Word	Noun	Adjective	Verb	Adverb
wrath	Yes	No	No	No
mortal sin	Yes	No	No	No

As nouns, mortal sin is a hypernym of wrath; that is, mortal sin is a word with a broader meaning than wrath:

wrath: belligerence aroused by a real or supposed wrong (personified as one of the deadly sins)
mortal sin: an unpardonable sin entailing a total loss of grace

Other hypernyms of wrath include deadly sin.

wrath (noun)	mortal sin (noun)
belligerence aroused by a real or supposed wrong (personified as one of the deadly sins)	an unpardonable sin entailing a total loss of grace
intense anger (usually on an epic scale)