The daily newspaper of the Italian Bishops Conference Avvenire has an article on p. A23 about the appearance of the Motu Proprio Summorum Pontificum in the official instrument of the Holy See for the promulgation of documents, Acta Apostolicae Sedis.
There are variations in the text of the Motu Proprio.
First, here is my translation of the piece in Avvenire with my emphases and comments. Then I will summarize the few, but in some ways, important changes to the Latin text.
Summorum Pontificum Published in the Acta
Mass in Latin [grrrrr]
The text of the Motu Proprio is in the "official gazette" of the Holy See. How requests for use of the Missal of 1962 in parishes where there is "stably" a group of faithful adhering to the pre-conciliar rite are to be received.
Yesterday Benedict XVI nominated as Vice President of the Pontifical Commission Ecclesia Dei, Msgr. Camile Perl, till now Secretary of the same Commission. At the same time the Pope nominated as Secretary Msgr. Mario Marini, until now Adjunct Secretary.
The Motu Proprio Summorum Pontificum, with which on 7 July 2007 Benedict XVI "derestricted" the use of the pre-conciliar Missale Romanum, was published in the Acta Apostolicae Sedis, the official gazette of the Holy See. The text of the document appears in the fascicle of the Acta distributed last week, that bears the date 7 September 2007, on pages 777-781. Together with is the accompanying letter that the Pope wrote to bishops of the Catholic Church of the Latin Rite.
On 22 September of last year Corriere della sera had a comment on p. 49 entitled "But is the Motu Proprio really on the back burner? (resta a bagno maria)". In it it was indicated that the document Summorum Pontificum had not yet been published in the Acta, "the instrument which gives force to papal provisions". The commentator in question, Prof. Alberto Melloni, after having referred to criticisms expressed by some ecclesiastics about the Motu Proprio in question, appears to appreciate the "wise decision still to keep on the back burner a text that is creating more problems than it resolves."
In reality, at the time the Motu Proprio was not published in the Acta for the simple fact that there had not been time enough to work out the technical issues. To tell the truth, the publication of the Motu Proprio was expected in the preceding fascicle of the Acta, that bore documents and pontifical appointments published between 27 May and 2 August 2007. Perhaps the brief delay for the publication was due to the fact that, compared to the version published on 7 July 2007, the definitive and binding version of the Motu Proprio Summorum Pontificum showed some small variations.
Above all, the Motu Proprio was given a subtitle (De uso [sic! It should be usu.] extraordinario antiquae formae Ritus Romani) that was not present before. In Article 1, then, the term "conditiones" was replaced with the more correct form "condiciones".
In Article 3 the term "plerumque" (the majority of times) was replaced with "habitualiter" (habitually), without however changing the substance of the disposition. [Not sure about that.]
The more concrete variation, on the other hand, is in Article 5,1: "In parishes in which there exists stably (stabiliter) a group of faithful adhereing to the preceding liturgical tradition, the pastor is to received willingly their requests for the celebration of Holy Mass according to the rite of the Missale Romanum published in 1962". In the original version, in place of the term "stabiliter" there was "continenter", which literally means "uninterruptedly" and which could cause one to think erroneously that the group of the faithful had the right to the "pre-conciliar" Mass only if it was stably established already before the publication of the Motu Proprio and not subsequent to it. [This is a significant change in meaning.]
Finally, another variation is found in Article 7: "If a group of the lay faithful, mentioned in art. 5,1, have not obtained to the request on the part of the pastor, let the Diocesan Bishop be informed about the matter. The Bishop is strenuously asked that he graciously grant their desire. If he does not want to provide for such a celebration, let the matter be referred to the Pontifical Commission "Ecclesia Dei". In this case the verb "non vult" replaces the original "non potest" (cannot). [Another fairly important change.]
To sum up the changes in the Latin text.
There is a subtitle: De uso extraordinario antiquae formae Ritus Romani ("On the extraordinary use of the old form of the Roman Rite"); [No significant meaning attached to that addition. Remember that in Latin, antiquus can also mean "former in time", not just "old" or "ancient".]
In Article 1, conditiones is replaced by condiciones. [The meaning of the Article does not change thereby.]
In Article 3, plerumque ("very often, for the most part") is replaced with habitualiter, a word found in juridical Latin, meaning "habitually", with the legal overtone that carries. [This could have an impact. But we need a canonist on this.]
In article 5, § 1, continenter ("continuously, uninterruptedly") is replaced with a term found in legal Latin stabiliter ("stably"). This is an important change in meaning. Effectively, stably says that the group has to be there for a while, and need not have been there in an uniterrupted way even before the Motu Proprio. So, new groups can form and emerge and then be around in a continuous way. What we still need to understand, however, is what "stable" means in terms of the group’s composition. One assumes reasonably that a group can grow or shrink. Hopefully this will be clarified now that we have the correct word. [This is big. It concerns the composition and presence of a group of faithful.]
In article 7, non potest ("cannot") is not non vult ("does not want"). There is a big difference between not wanting to do something and not being able to do something. We are all able to do things we would prefer not to do. So, if a priest is capable, if a bishop is capable, but does not want to do something for the requests of lay people, the matter goes to Rome. In other words, if the cleric is capable, and the means are there, there is even less excuse not to receive petitions positively than there was when the words were non potest. [This is also big. It concerns the attitude of those who receive petitions, the available means, and ability of the clerics concerned.]
In a way, the change to stabiliter and non vult strengthen the rights of lay people in this regard. I don’t really understand the ramifications of the juridical sounding habitualiter (a dreadful Latin word).