You misunderstand what the Church teaches. Penance does not atone for anything. After the sin is forgiven in a sacramental confession, the priest assigns penance for the benefit of the penitent, but the sin is forgiven the moment the priest absolves it, and not after the penance is done. This is a common misunderstanding.
making other dogmas necessary elements which absolutely must be believed in order to be saved
This is right in the Nicene Creed though. Credo unam sanctam catolicam apostolicam ecclisiam. Bind and loose.
disputed as spurious
Duh. We live in the age of charlatans.
the original says, "repentance".
The original says "metanoiete", which literally means "change your mind". The question is which translation is best reflecting the intention of the speaker, and since St. John who issued the call can best be described as doing penance rather than thinking repentant thoughts, Douay (it actually follows Jerome's "penitentiam agite") is the most accurate in essence.
You misunderstand what the Church teaches. Penance does not atone for anything. After the sin is forgiven in a sacramental confession, the priest assigns penance for the benefit of the penitent, but the sin is forgiven the moment the priest absolves it, and not after the penance is done. This is a common misunderstanding.
Then someone needs to correct Ludwig Ott, John Hardon and a host of other Roman Catholics, including the Council of Trent because that is exactly what they state of penance, being the atonement or reparation or expiation of sins committed after baptism.
Duh. We live in the age of charlatans.
Yes, as the fraudulent forgeries Rome has used to assert authority it never had, such as the Donation of Constantine, Liber Pontificallis, and Pseudo-Isidorian Decretals prove of the charletans in the Roman Catholic religion.