In ‘Unam sanctam’ Pope Boniface VIII stated: “… we declare, we proclaim, we define that it is absolutely necessary for salvation that every human creature be subject to the Roman Pontiff.”
Actually, and it’s probably been pointed out here already, it’s been infallibly and specifically proclaimed at least three times in Church history:“One indeed is the universal Church of the faithful, outside which no one at all is saved.” (IV Lateran Council, A.D. 1215)
“We declare, we say, we define, and we pronounce that it is wholly necessary for the salvation of every human creature to be subject to the Roman Pontiff. The Lateran, November 14th, in our eighth year. As a perpetual memorial of this matter.” (Unam Sanctam, A.D. 1302)
“It [the Holy, Catholic, and Apostolic Church] firmly believes, professes, and proclaims that none of those outside the Catholic Church, not only pagans, but neither Jews, nor heretics and schismatics, can become participants in eternal life, but will depart “into everlasting fire which was prepared for the devil and his angels” [Matt. 25:41], unless before the end of life they have been added to the Church; and that the unity of the ecclesiastical body is so strong that only to those remaining in it are the sacraments of the Church of benefit for salvation, and do fastings, almsgiving, and other functions of piety and exercises of Christian service produce eternal reward, and that no one, whatever almsgiving he has practised, even if he has shed [his] blood for the name of Christ, can be saved, unless he has remained in the bosom and unity of the Catholic Church.” (Pope Eugenius IV, A.D. 1431-1447, at Council of Florence,
Cantate Domino, A.D. 1442)
In This obviously means only Catholics can be saved, no?
Um, yes. They would be catholic by being incorporated into the mystical body of Christ - the Catholic Church. There has always been understood certain conditions wherein one could be possibly connected to the Church without a visible (to our eyes) connection - but common sense tells us it is rare and difficult.
Problem is, nowadays, folks tend to make the rare and difficult not-so-rare, and not-so-difficult.
Here’s a pretty good article covering the topic:
Questions and Answers on Salvation, by Father Michael Muller, C.SS.R
and another one:
Invincible or Inculpable Ignorance Neither Saves nor Damns a Person, by by Father Michael Müller, C.Ss.R.
Peace in Christ,
DustinsDad