Where exactly does the Council say that those at the end of their lives who die outwith the Church can attain unto eternal salvation? On the contrary the Council teaches that those can also attain to eternal salvation who are moved by grace strive by their deeds to do His will and we know that it is God’s will that all persons be joined to His Church. The graces they are given are the graces that will lead them to the Church. If they are honest, of good will, and seek God then God will grant them the graces to be led to His Church. And isolation is no barrier to the will of God. Did God leave the Ethiopian eunuch to flounder on His own? No! He sent Philip the Deacon to assist him in his salvation.
The Council does not teach salvation for non-Catholics. She joyfully proclaims that non-Catholics through the will and providence of God can be brought to the means of salvation, the Holy Catholic Church as we see further on in the same passage from Lumen Gentium…
What is necessary for salvation? “Jesus answered: Amen, amen I say to thee, unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God.” (John. 3: 5). Christ Himself has told us what is necessary to enter into the kingdom of God. And Hebrews 11: 6 tells us that “…] without faith it is impossible to please God. For he that cometh to God, must believe that he is, and is a rewarder to them that seek him.”
Saint Thomas Aquinas tells us that “After the Incarnation, all men, if they wish to be saved, are “bound to explicit faith in the mysteries of Christ, chiefly as regards those which are observed throughout the Church and publicly proclaimed, such as the articles that refer to the Incarnation.” And further that all men, in order to be saved, “are bound to explicit faith in the mystery of the Trinity.”
Is this not enough for you? I have given you Scripture. I have given you the Angelic Doctor. Then I shall finish this point with the Magisterium herself expressed by the Second Vatican Council in her Decree on the Mission Activity of the Church or Ad Gentes.
"…those men cannot be saved, who though aware that God, through Jesus Christ founded the Church as something necessary, still do not wish to enter into it, or to persevere in it. **Therefore though God in ways known to Himself can lead those inculpably ignorant of the Gospel to find that faith without which it is impossible to please Him **(Heb. 11:6), yet a necessity lies upon the Church (1 Cor. 9:16), and at the same time a sacred duty, to preach the Gospel.”
Lumen Gentium is not only clarified by the light of the Church’s tradition but by a document of the very same ecumenical council. Ad Gentes clearly teaches that God can lead people to that which is necessary for salvation. No where in this document or in Lumen Gentium or in any Magisterial document of the Church is it taught that someone can attain to salvation that perishes in a state of invincible ignorance outside of the Church or that those baptised Christians that reject the Church can enter into the kingdom of God. Rather we are told that the Church has a necessity and a sacred duty to preach the Gospel and bring people to the knowledge of God and the means of salvation [herself] and that in ways known to God He can bring such people to that which is necessary. And we know that it is necessary to be a baptised Christian subject to the Holy Roman Pontiff.
But I did not even have to seek out Ad Gentes to kill your point. As Lumen Gentium itself finishes it here. This speaks volumes. Why would someone need to be prepared for the Gospel if it was unnecessary for salvation? Come now my friend.
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