The reason you do "penance" is because Jerome mistranslated "Repentance" as "Penance".
Martin Luther, at that time, read this.....as He was also a "Catholic Translator".. and he realized that Jerome was
mistranslating according to Jerome's point of view.... that denied God's Grace.
So, we can thank JEROME for helping the "protestant" reformation = come into existence, ......while you can thank Jerome for putting a man made NT rejecting burden on you, for most of your Life.
See what happens when you are trapped by a Cult?
Done any penance lately
@Marymog ?
You will...., and you can thank JEROME for that unscriptural behavior the next time you are lightning a candle for "perpetual virgin" Mary.