1 Certain people came down from Judea to Antioch and were teaching the believers: “Unless you are circumcised, according to the custom taught by Moses, you cannot be saved.” 2 This brought Paul and Barnabas into sharp dispute and debate with them.
1 Certain people came down from ROME and were teaching the believers: “Unless you do such and such, according to the custom taught by the ONLY 'true' church, you cannot be saved.” 2 This brought folks who knew better into sharp dispute and debate with them.
It is only by grace that we are saved. What the Church teaches is what one must do to be in full communion with the Church and participate in all the Sacraments Jesus gave for our sanctification.
All the other sacramentals, prayers and such are recommended for our spiritual health. They are not requirements. No one has to pray to Mary. No one has to pray the rosary. No one has to venerate saints.