Pius XII as Pacelli worked on the Code of Canon Law in 1917. That involved a lot of changes.
Then Pius XII permitted Holy Mass to be celebrated in the vernacular during World War II in England, France, and Germany. Since people in Europe got used to hearing the Mass in the vernacular, was it no surprise that this New Mass would be forced on us? Pius XII was no dummy.
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Prior to the first Code of Canon Law (1917) there had never been any such Code. So there had been nothing to "change."
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The enormity and devastation of WWI had profoundly affected then Bishop Eugenio Pacelli, which is evident from the fact that he was a close associate of Benedict XV and of Pius XI, whose writings are readily available to read. When Pius XII first came to office Europe was obviously on the verge of another great war, and Pius XII was right in the middle of it. He must have been terrified. It's not impossible to see that his allowing the Mass to be vernacularized in some places had been an act of desperation. Keeping the Mass in Latin didn't help avoid WWI, after all. Why would it help avoid WWII?
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Finally, Pius XII established Diocesan Liturgical Commissions throughout the world when he published his encyclical Mystici corporis Christi on 29 June 1943. If the Mass were not broken, why would Pius XII ask all dioceses to establish these diocesan liturgical commissions? What was the purpose of these commission? These commissions ultimately paved the way for the disastrous Vatican II council and the Novus Ordo.
Yes, I realize that the initial papers for Vatican II were much better than the final drafts. Nevertheless, it was Pius XII who initiated the plans for Vatican II, and it was he who initiated all the changes in the Code of Canon Law of 1917.
I have read the encyclical Mystici corporis Christi several times. First for my college classes, then in a study group, and finally as a review. I was never impressed by it as it seemed so deceptive.
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When Pius XII set up the liturgical commissions he was trying something new in hopes of finding a solution to the numerous problems the world was facing, and he no doubt had problematic advisers. The solution he was groping for could have easily been achieved by making the Collegial Consecration of Russia together with all the bishops of the world. For whatever reason, he apparently listened to his advisers instead of to the actual request of Our Lady. This is very mysterious.
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The language of
Mystici Corporis Christi was beginning to resemble that which was used throughout Vat.II. While the things that he said in the encyclical are very good things, the WAY he said them was a bit different, and in retrospect could have been better. Also, there were some issues that Pius XII fell short of addressing at the time which he did for whatever reasons, but later they would become opportunities for the Church's enemies to make progress against the Church. It seems to me that he was trying to make accommodation to the modern world, expecting that would help encourage world peace. He lent his ear also to impostors, perhaps by mistake, and I think he had good intentions but was under enormous pressure to modernize things. Being Pope in those days was no walk in the park.
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If it was difficult to be Pope in those days, imagine how difficult it would be TODAY. Blessed Jacinta Marto had it right when she advocated prayer and sacrifice for the Holy Father.
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Perhaps
the worst effect of sedevacantism is that it deprives the current pope from prayers of Catholics. That many more Masses are said without mention of prayers for the Holy Father (because of the
"una cuм" dissension).
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