Before Vatican II, the Church consistently taught that only Roman Catholics had a chance to be saved and attain Heaven. Followers of other Christian denominations and of other religions would be automatically routed to Hell for all eternity:
* Pope Innocent III (circa 1160 - 1216 CE) is considered “one of the greatest popes of the Middle Ages...” 1 At the Fourth Lateran Council (a.k.a. the General Council of Lateran, and the Great Council) he wrote:
“There is but one universal Church of the faithful, outside of which no one at all can be saved.”
* Pope Boniface VIII (1235-1303 CE) promulgated a Papal Bull in 1302 CE titled Unam Sanctam (One Holy). He wrote, in part:
“Urged by faith, we are obliged to believe and to maintain that the Church is one, holy, catholic, and also apostolic. We believe in her firmly and we confess with simplicity that outside of her there is neither salvation nor the remission of sins...In her then is one Lord, one faith, one baptism [Ephesians 4:5]. There had been at the time of the deluge only one ark of Noah, prefiguring the one Church, which ark, having been finished to a single cubit, had only one pilot and guide, i.e., Noah, and we read that, outside of this ark, all that subsisted on the earth was destroyed....Furthermore, we declare, we proclaim, we define that it is absolutely necessary for salvation that every human creature be subject to the Roman Pontiff.” 2
The last sentence in the original Latin reads: “Porro subesse Romano Pontifici omni humanae creaturae declaramus, dicimus, definimus, et pronuntiamus omnino esse de necessitate salutis.” 3
* Pope Eugene IV, (1388-1447 CE) wrote a Papal bull in 1441 CE titled Cantate Domino. One paragraph reads:
“It [the Church] firmly believes, professes, and proclaims that those not living within the Catholic Church, not only pagans, but also Jews and heretics and schismatics cannot 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 the same have been added to the flock; 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 practiced, even if he has shed blood for the name of Christ, can be saved, unless he has remained in the bosom and unity of the Catholic Church.” 4
It couldn't be more clear.
Jesus Christ was very clear when he said "MY Church", why would you want to pluralize something that God clearly said was singular. Additionally, the Church does not teach that Orthodox or Protestants are outside salvation; Innocent III was very purposeful saying "Church of the faithful," our faith is in God.
As far as Unam Sanctum, are you suggesting that Jesus Christ was LYING when in Matthew 16:19?
The controversial part (to me) was that to be a member of that body is to be saved.
This could be expressed as IF you are a member of this body THEN you are saved -- Or -- every member of the set of members of the body is a member of the set of saved people.
Now when I look at the quotes you provide, i do not see that. I see at most IF you are NOT a member of the body, then you are NOT saved -- Or -- every member of the set of people NOT members of the body is also a member of the set NOT saved people.
These two propositions are not identical.
For: Let's play with squares and rectangles.
IF you are a square, you are a rectangle.
BUT that is NOT the same as
If you are NOT a square, you are not a rectangle.
So, looking at the logic, Saying "if you are not in the body you are not saved"
is NOT the same as saying
If you are in the body you are saved.
So the quotes you provided do not support your contention.
QED