English translation of the February 26, 1949 letter Monsignor Giovanni Battista Montini, then Substitute Secretary of State of the Holy See and later Pope Paul VI, wrote in the name of His Holiness Pope Pius XII to Prof. Plinio Corrêa de Oliveira in appreciation for his book, In Defense of Catholic Action.
Vatican, February 26, 1949
Illustrious Sir,
Moved by filial dedication and piety, you have offered to the Holy Father the book titled In Defense of Catholic Action, written by you with exemplary care and persevering diligence.
His Holiness rejoices with you, for you have so keenly and eloquently explained and defended Catholic Action—an apostolate which you thoroughly understand and deeply esteem—making clear to all how this auxiliary form of the hierarchical apostolate ought to be examined and carried out.
The August Pontiff prays with all his heart that your labor may bear abundant fruit, and that the consolations you reap from it may be neither small nor few. In pledge of these favors, He imparts to you His Apostolic Benediction.
In the meantime, with due consideration, I remain,
Devotedly yours,
G. B. Montini
Substitute Secretary of State