By Michael Pakaluk

Next year will be the 75th anniversary of Munificentissimus Deus, "The Most Bountiful God," the encyclical of Pius XII in which he defined (November 1, 1950) the doctrine of the Assumption of Mary body and soul into Heaven. Most Catholics know that this document represents the second of only two occasions on which a Roman Pontiff exercised his authority to define doctrine infallibly. It should be very important, then. But chances are, you have never read it. If so, may I suggest that sometime today you study it, on this great Solemnity, and that you even consider making it a kind of "companion" in the coming year, leading up to the anniversary? Its teaching is highly edifying - and surprising.

Right from the start, its tone is surprising. It comes to us from the other side of that great divide that is the 1960s. Showing not the slightest signs of that glib dismissal of sin and giddy faith in progress that have marked our own time, it views the human condition as a series of "anxieties, cares, and troubles" into which, from time to time, God interposes consolations.

Prominent among these is that "the Catholic faith is being professed publicly and vigorously" and that "piety toward the Virgin Mother of God is flourishing and daily growing more fervent." Hence another note of the encyclical which is pleasantly surprising (to me at least), namely, its profound rejection of materialistic philosophy.

At the end of the encyclical, Pius rejoices that he has been able "to adorn the brow of God's Virgin Mother with this brilliant gem, and to leave a monument more enduring than bronze of our own most fervent love for the Mother of God." And I rather think that if you had asked him which was the greater gift and consolation to the people of God, the definition of the Assumption, or a great basilica such as St. Mary Major, he would have said the former.

Another surprising fact about the encyclical is that the "development of doctrine" is never invoked. Newman's notes of a "genuine development" are never referred to, even implicitly. Rather, it is clearly Pius's view, and clearly his view of everyone else's view, that the Assumption of Mary has always been a truth of the Catholic faith, from the very beginning.

What is the "definition" then? What does the pope actually accomplish in the encyclical? Here's the kind of thing that someone might imagine happens: a pope with his advisors (maybe the head of the DDF, or "small study circle" within the PAL) sit around and cogitate about some new realization which they believe, perhaps in light of the "signs of the times" - although it was never held before, or certainly not by everyone - follows from the Gospel. They then test out this new teaching with some bishops, and, if no one ubjects, the pope can put it forward as a "development of doctrine." And as he is infallible, there's no taking it back.

Pius takes himself to be doing something very different. He thinks that everyone always held to the Assumption as true. To define the Assumption is simply to change the standing of that truth. As a result of the encyclical, the Assumption moves from being simply a deep truth that everyone sees is true, to being a deep truth that the Church formally proposes as true and requires everyone to believe as belonging to the deposit of faith.

That is why only at the end of the encyclical, and not before - only after the doctrine has been "defined" - that Pius can say "Hence if anyone, which God forbid, should dare willfully to deny or to call into doubt that which we have defined, let him know that he has fallen away completely from the divine and Catholic Faith."

Hence another surprising trait of the encyclical - surprising given what the Church's critics say - namely, Pius's frequent affirmations that he is bound by the rule of Scripture, and that he is a custodian of the deposit of faith and has no authority to teach anything outside that deposit. His whole manner of proceeding - caref...