penance vs self-abasement

penance and self-abasement both are nouns.

Word	Noun	Adjective	Verb	Adverb
penance	Yes	No	No	No
self-abasement	Yes	No	No	No

As nouns, penance and self-abasement are synonyms defined as:

penance and self-abasement: voluntary self-punishment in order to atone for some wrongdoing

Other synonyms of penance include self-mortification.

penance (noun)	self-abasement (noun)
voluntary self-punishment in order to atone for some wrongdoing	voluntary self-punishment in order to atone for some wrongdoing
a Catholic sacrament; repentance and confession and atonement and absolution
remorse for your past conduct