When the time of persecution and purification of the Church comes, which Ralph Martin mentioned, it would be useful and important for Catholics to be able to know and affirm the Faith, and say like St. Thomas Aquinas that outside the Catholic Church there is no salvation

 When the time of persecution and purification of the Church comes, which Ralph Martin mentioned, it would be useful and important for Catholics  to be able to know and affirm the Faith, and say like St. Thomas Aquinas that outside the Catholic Church there is no salvation. -Lionel Andrades