General Catholic
Can non-Catholics be saved?
Yes — the Church teaches that those who, through no fault of their own, do not know Christ or his Church, but sincerely seek God and follow their conscience, can attain salvation by grace, even as the fullness of the means of salvation subsists in the Catholic Church.
Catholic teaching
Lumen Gentium teaches that baptized non-Catholic Christians are truly, if imperfectly, joined to the Church, and that even those who have not received the Gospel but sincerely seek God and strive to do his will as known through conscience may achieve eternal salvation, all such salvation ultimately being through Christ's grace, even if unrecognized as such by the person.
Biblical foundation
Peter declares 'in every nation any one who fears him and does what is right is acceptable to him' (Acts 10:34-35), and Paul teaches that Gentiles without the law can still 'do by nature what the law requires' by the law 'written on their hearts' (Rom 2:14-15), grounding the possibility of salvation for the sincere who lack full knowledge through no fault of their own.
Scripture references
Historical evidence
This teaching is not a modern innovation but develops the ancient principle, already discussed by Justin Martyr in the second century, of the 'seeds of the Word' (logos spermatikos) present among peoples before or apart from explicit knowledge of Christ, showing deep roots in the Church's earliest theological reflection.
The Church Fathers
“Whatever things were rightly said among all men are the property of us Christians... for all the writers were able to see realities darkly through the sowing of the implanted word that was in them.”