CM asked me to share my thoughts in a letter to him about MCC.  I've been putting this off for too long, so here is a quick stab at this troubling encyclical, which I will offer for public consumption.

Firstly, a correction.  I had said in another thread that this was evidence in favor of Feeneyism --

"Actually only those are to be included as members of the Church who have been baptized and profess the true faith, and who have not been so unfortunate as to separate themselves from the unity of the Body, or been excluded by legitimate authority for grave faults committed."

It turned out that was due to the English translation, where "Actually" looks like a conjunctive adverb.  The Latin sentence should be translated more like "Only those are ACTUAL ( reapse ) members of the Church who have been baptized and profess the true faith..." etc.  Pius XII was borrowing directly from Bellarmine, from real ( reapse ) vs. voto membership, and leaving open the possibility of membership by desire.

Pius XII even goes on to refer to Bellarmine specifically.

"As Bellarmine notes with acuмen and accuracy,[93] this appellation of the Body of Christ is not to be explained solely by the fact that Christ must be called the Head of His Mystical Body, but also by the fact that He so sustains the Church, and so in a certain sense lives in the Church, that she is, as it were, another Christ."

It is very possible, especially for Feeneyites, to read a sinister design in Pius XI's canonization of Bellarmine, which was followed by Pius XII's attempt to dogmatize the re vs. voto membership concept from the Chair of Peter.  

Ladislaus, this raises more problems for you than for me, because if you accept Pius XII as a true Pope, this encyclical makes baptism of desire, in some form, a dogma, unless it is possible to completely ignore teaching on a crucial matter of faith from an encyclical that is considered to be authoritative and important.

*****

Moving on to the famous or infamous paragraph 103 --

103. As you know, Venerable Brethren, from the very beginning of Our Pontificate, We have committed to the protection and guidance of heaven those who do not belong to the visible Body of the Catholic Church, solemnly declaring that after the example of the Good Shepherd We desire nothing more ardently than that they 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.

Does this teach implicit faith or not?  That is the question.

Those who "don't belong to the visible body of the Catholic Church" could be catechumens.  However, Pius XII nixes that idea when he later goes on to talk about those who are related to the Church by an "unconscious desire and longing."  Since he says these "cannot be sure" of their salvation, that means that, according to him, those who do not have a conscious desire to join the Catholic Church can be saved.  What is very disturbing is that he practically extends this to universal salvation by saying, as if it were a fact, that "they have a certain relationship with the Mystical Body of the Redeemer."  What, all of them?  And who is "they," anyway?

This ambiguity may keep the encyclical from heresy or error, depending on your EENS position.  It doesn't specifically teach implicit faith, since by those with an "unconscious desire and longing" it could be referring to those who believe in the Trinity and Incarnation, who believe the essential basics of the faith, but who are not aware of the Catholic Church.  Such people would be invincibly ignorant Protestants or poorly catechized heathens, I guess.  

"Implicit faith" as it's usually defined is having an implicit faith in the Trinity and Incarnation, while having an implicit desire to join the Church would probably qualify more as "implicit baptism of desire."  So I would say that Pius XII is teaching implicit BoD, but not implicit faith, in this letter.

Of course, if you believe that Pius XII approved of Suprema Haec Sacra, which teaches that Pius XII did intend MCC to teach implicit faith, well -- that still doesn't mean anything, unless we have to believe that a non-authoritative letter can give us an authoritative interpretation of an encyclical.  This brings up a big question:  Does the truth of an encyclical depend on what the Pope INTENDED or on what it actually SAYS?  

Since he says these "cannot be sure" of their salvation, that means that, according to him, those who do not have a conscious desire to join the Catholic Church can be saved.

It doesn't mean that at all.  Even Catholics "cannot be sure" of their salvation.  People who are "tending towards" the Church are on the via salutis, as it's called I think in the catechism of St. Pius X.  They are on the "road to" salvation.  Using the terminology "on the road to" actually implies that they are not at their destination yet.  So it's a completely open and ambiguous phrase that does not necessarily imply that they can be saved if they died in their current state.  There's no inherent implication that they could be saved if they died in this state, but it leaves itself open to that interpretation (i.e. it doesn't actively eliminate it either).

I think that they key to understanding this troublesome phrase is to realize that even we Catholics "cannot be sure" of our salvation.  So in becoming Catholics they would then be sure of their salvation?  No, of course not.

I'm guessing there's a translation problem.  In the Latin I find the word securi.  Later, the word "relationship" is actually a translation of their being "ordered toward".

Securi means to be free from care or concern.  But Catholics are not free from care or concern about their salvation in the strict sense.  So this is a bit tough here.

So the key to understanding is to determine in what way Catholics are "free from care or concern" about their salvation.

It's because unlike the others, members of the Church have "many heavenly gifts and helps", that being the sacraments. That's how I understand it at least.