I appreciate your charitable demeanor and consideration that Non-Catholic Christians ARE really Christians. You say that this is a "doctrine of my church". In light of that, how does a Catholic explain the supposedly "infallible" statements from Popes such as:
“We declare, say , define, and pronounce that it is absolutely necessary for the salvation of every human creature to be subject to the Roman Pontiff.” Pope Boniface VIII, Unam Sanctam (1302 AD)
Can such a declaration just be ignored? Was Pope Boniface saying something that is NOT true or is it just not true anymore and the Catholic Church changed her mind? I am not trying to play any game here. I just wonder how Catholics can say all "true" Christians must follow the Pope to be saved but then concede that non-Catholics can also be saved who don't follow the Pope of Rome? How is this not a contradiction?
Found on a random Catholic forum.
The short answer is that the quote in bold type is true, but cannot be be understood outside of the context of how the Catholic Church defines mortal sin. For an act to be a mortal sin --- and the sinner deprived of salvation ---
So if Christ seriously intends for there to be "one flock and one shepherd," (John 10:16) and if this means the Catholic Church and the successor of Peter (to whom Christ --- three times ---gave the job of "feeding my sheep"), hence if Peter and his successors are chief shepherds --- three "if's" --- then it would be objectively wrong ("grave matter") for any person to fail to enter this Church, or to fail to remain in it, or to fail to be subject to Peter's successor, whosoever that might be.
In Biblical terms, it's evil for there to be split-up flocks and competing shepherds, when Christ's intention was for "one flock and one shepherd."
OK. Does that mean all non-Catholics are in mortal sin and have forfeited their salvation?
In a word, No.
This is because the two other elements of a mortal sin are not present: the "separated brethren" are almost always people who
In other words, element #1 (grave matter) is present, but not element #2 (knowledge of the mind) and element #3 (consent of the will).
Pope Pius IX in his teaching on "invincible ignorance" pretty much destroyed the interpretation that Unam Sanctum meant that non-Catholics cannot be saved. Pius IX pointed out that it was possible for one to
Although Pius IX's teaching was five or six centuries after Boniface, the concept of invincible ignorance is much older, and should always have been (correctly) applied to the teachings of Unam Sanctam, and, indeed, to every moral teaching. Aquinas references "invincible ignorance" in his Summa Theologica (written in the 1200's, half a century before Pope Boniface's statement) and it's even in the writings of third-century Fathers.
I bolded the word "visible" Church because there are ways to be part of the Church without being part of the "visible" Church. Baptism of desire is one way, and it means desiring to do whatever is needed in order to honor God, do His will, appeal for His mercy, and enter His kingdom (you could say the Good Thief on the "other cross" did that). In the case of the "separated brethren," any valid baptism joins one certainly (even if imperfectly) to the Church since there is one Faith, one Lord and one Baptism.
BTW, this interpretation may be controversial (there are plenty of FReepers who would supply controversy!) but it is not unreasonable. It has reasons. It makes sense if you accept the premises.
Not should it be seen as insulting. We're all baptized sinners --- you, me, this pope and the next one. Saved by Christ, by grace, by the mercy of God. We all know that.