I wanted to share some things with you about the whole business of Ratzinger and his statement about how non-Catholic religions are “gravely deficient.” I know that the issue of salvation outside the Church is one which is very important to you (it’s important to me, too); I’ll underline the important parts of quotes and try to keep things simple.
There are two important Church documents about this issue, and each of these has a few important points.
The one that people are talking about is called “Dominus Iesus: On the Unicity and Salvific Universlity of Jesus Christ and the Church.” It was written by Ratzinger and promulgated in 2000. In it, he wrote,
" 22. With the coming of the Saviour Jesus Christ, God has willed that the Church founded by him be the instrument for the salvation of all humanity (cf. Acts 17:30-31).90 This truth of faith does not lessen the sincere respect which the Church has for the religions of the world, but at the same time, it rules out, in a radical way, that mentality of indifferentism “characterized by a religious relativism which leads to the belief that ‘one religion is as good as another’”.91 If it is true that the followers of other religions can receive divine grace, it is also certain that objectively speaking they are in a gravely deficient situation in comparison with those who, in the Church, have the fullness of the means of salvation.92"
There’s a few footnotes in there. Footnote #92 refers to “Mystici Corporis Christi: Encyclical of Pope Pius XII on the Mystical Body of Christ.” It was promulgated in 1943.
Ratzinger is drawing upon the teaching of Pius XII. Pius wrote,
" We desire nothing more ardently than that they [non-Catholics and non-Christians] may have life and have it more abundantly. Imploring the prayers of the whole Church We wish to repeat this solemn declaration in this Encyclical Letter in which We have proclaimed the praises of the “great and glorious Body of Christ” and from a heart overflowing with love We ask each and every one of them to correspond to the interior movements of grace, and to seek to withdraw from that state in which they cannot be sure of their salvation. For even though by an unconscious desire and longing they have a certain relationship with the Mystical Body of the Redeemer, they still remain deprived of those many heavenly gifts and helps which can only be enjoyed in the Catholic Church. Therefore may they enter into Catholic unity and, joined with Us in the one, organic Body of Jesus Christ, may they together with us run on to the one Head in the Society of glorious love. Persevering in prayer to the Spirit of love and truth, We wait for them with open and outstretched arms to come not to a stranger’s house, but to their own, their father’s home."
Now, these documents are very different from one another. They were written in very different times, by different offices, to different audiences, for different reasons.
The main problem for Pius XII was the idea of the “invisible Church.” The idea was originally thought up by Protestants who wanted to figure out what was going on between the 4th century (when the Church ‘corrupted’ and became the ‘whore of Babylon’) and the Protestant Reformation (when ‘everything was fixed’ and ‘true Christianity’ came back). You see, Protestants can’t say that the Church was dead for 13 centuries, because that contradicts the Bible (“upon this rock I will build my church, and the gates of the netherworld shall not prevail against it.” [Matt 16:18]). So, instead of saying that the Church was dead for 13 centuries, Protestant theologians started saying that the Church was “invisible.”