10 An effort has been made to strike the Church in a still more vital spot; namely, in the existence of the clergy and the Catholic hierarchy, by trying to eliminate it gradually from the Republic. Thus the Mexican Constitution, as We have several times deplored, while proclaiming liberty of thought and conscience, prescribes with the most evident contradiction that each State of the Federal Republic must determine the number of priests to whom the exercise of the sacred ministry is allowed, not only in public churches, but even within private dwellings. This enormity is further aggravated by the way in which the law is applied. The Constitution lays down that the number of priests must be determined, but ordains that this determination must correspond to the religious needs of the faithful and of the locality. It does not prescribe that the Ecclesiastical Hierarchy is to be ignored in this matter, and this point was explicitly recognized in the declarations of the modus vivendi . Now in the State of Michoacan one priest was assigned for every 33,000 of the faithful, in the State of Chiapas one for every 60,000, while in the State of Vera Cruz only one priest was assigned to exercise the sacred ministry for every 100,000 of the inhabitants. Everyone can see whether it is possible with such restrictions to administer the Sacraments to so many people, scattered for the most part over a vast territory. Indeed, the persecutors, as though sorry for having been too liberal and indulgent, have imposed further limitations. Some Governors closed seminaries, confiscated canonries, and determined the sacred buildings and the territory to which the ministry of the approved priest would be restricted.
Source: Acerba Animi (Vatican.va)