This time in Church history is an important time to recover the documents of the pre-Vatican II popes. In reading Pope Pius IX's encyclical 'Quanto Conficiamur Moerore' (On Promotion Of False Doctrines) we see the clear teaching of the Church concerning salvation for those outside the Church as well as the necessity of their conversion. When is the last time you have heard this preached? Below are paragraphs six through nine of the document. We must as Catholics be prepared to deal with the modernists now found in every corner of the Church trying to deceive the faithful.
6. Now, since our Apostolic Office demands we carefully and zealously defend the cause of the Church committed to us by Christ, we condemn those who attack and despise the Church itself, its sacred laws, ministers, and this Apostolic See. Hence, with this letter, once more we confirm, proclaim and condemn totally and singly that which in many consistorial allocutions and in our other Letters we have been forced to deplore, declare and condemn.
7. Here, too, our beloved sons and venerable brothers, it is again necessary to mention and censure a very grave error entrapping some Catholics who believe that it is possible to arrive at eternal salvation although living in error and alienated from the true faith and Catholic unity. Such belief is certainly opposed to Catholic teaching. There are, of course, those who are struggling with invincible ignorance about our most holy religion. Sincerely observing the natural law and its precepts inscribed by God on all hearts and ready to obey God, they live honest lives and are able to attain eternal life by the efficacious virtue of divine light and grace. Because God knows, searches and clearly understands the minds, hearts, thoughts, and nature of all, his supreme kindness and clemency do not permit anyone at all who is not guilty of deliberate sin to suffer eternal punishments.
8. Also well known is the Catholic teaching that no one can be saved outside the Catholic Church. Eternal salvation cannot be obtained by those who oppose the authority and statements of the same Church and are stubbornly separated from the unity of the Church and also from the successor of Peter, the Roman Pontiff, to whom “the custody of the vineyard has been committed by the Savior.” The words of Christ are clear enough: “If he refuses to listen even to the Church, let him be to you a Gentile and a tax collector;” “He who hears you hears me, and he who rejects you, rejects me, and he who rejects me, rejects him who sent me;” “He who does not believe will be condemned;” “He who does not believe is already condemned;” “He who is not with me is against me, and he who does not gather with me scatters.” The Apostle Paul says that such persons are “perverted and self-condemned;” the Prince of the Apostles calls them “false teachers . . . who will secretly bring in destructive heresies, even denying the Master. . . bringing upon themselves swift destruction.”
9. God forbid that the children of the Catholic Church should even in any way be unfriendly to those who are not at all united to us by the same bonds of faith and love. On the contrary, let them be eager always to attend to their needs with all the kind services of Christian charity, whether they are poor or sick or suffering any other kind of visitation. First of all, let them rescue them from the darkness of the errors into which they have unhappily fallen and strive to guide them back to Catholic truth and to their most loving Mother who is ever holding out her maternal arms to receive them lovingly back into her fold. Thus, firmly founded in faith, hope, and charity and fruitful in every good work, they will gain eternal salvation.