In his most recent extensive interview, the Superior-General of the Priestly Fraternity of Saint Pius X (FSSPX / SSPX), Bishop Bernard Fellay, talks to Brian Mershon - the only print journalist who did not miss a single beat regarding the motu proprio - on the release of Summorum Pontificum and on prospects for the future.
On Summorum:
I think we have to salute and to greet this date and this motu proprio as a very significant historical event in the history of the Church and in post-Vatican II history. This has to be noted. I think it is very important.
Nevertheless, this does not mean it is perfect—especially when we link the motu proprio with the letter [to the bishops]. The letter is, if I may say it, the usual Vatican language. It is very unfortunate.
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But nevertheless, this letter has to be understood as a political letter which most surely does represent his personal thinking. Nevertheless, it is more than unfortunate in many ways, especially where he insists upon the necessity to recognize the value and the holiness of the New Mass. He plays both sides against each other. And the modern bishops that are progressive—they will jump on that point immediately trying to dismantle the motu proprio.
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...this motu proprio is a step in our direction. It is most probably the will of Rome to answer to our first precondition. It is nice.
Is it enough to say, “We can now just go ahead?” Well, we can just look at this text published today [on the nature of the Church from the CDF] and you have the answer.
Look. It is a good step forward, but that does not mean that everything is solved. Absolutely not.
On the lifting of the excommunications of the Bishops consecrated by Archbishop Lefebvre in 1988:
The second point on the Roman side: as far as I know, they consider the [lifting of the decrees] of excommunication less difficult than the motu proprio. That’s the only answer I can give you. ... It is the word of Cardinal Castrillón [in the letter] when he sent me the motu proprio [the week before Summorum Pontificum was issued]. That is the first contact of the Cardinal with me since the 15th of November 2005.
On the SSPX and schism:
... in the [Pope’s] letter that accompanies the motu proprio on the Mass ...the Holy Father says it is an internal matter within the Catholic Church — in the Church.
It clearly states that it is not about a schism. It is about an interior dispute which requires an interior reconciliation within the Church.
So we have it from the word of the boss. Our Pope says it is not a schism.
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Read also: original text of the short interview granted by Fellay to Vittorio Messori - Corriere della Sera (in Italian).