7 When, therefore, in 1929 the Supreme Magistrate of Mexico publicly declared that the Government, by applying the laws in question, had no intention of destroying the "identity of the Church" or of ignoring the Ecclesiastical Hierarchy, We thought it best, having no other intention but the good of souls, to profit by the occasion, which seemed to offer a possibility of having the rights of the Hierarchy duly recognized. Seeing, therefore, some hope of remedying greater evils, and judging that the principal motives that had induced the Episcopate to suspend public worship no longer existed, We asked Ourselves whether it were not advisable to order its resumption. In this there was certainly no intention of accepting the Mexican regulations of worship, nor of withdrawing Our protests against these regulations, much less of ceasing to combat them. It was merely a question of abandoning, in view of the Government's new declarations, one of the methods of resistance, before it could bring harm to the faithful, and of having recourse instead to others deemed more opportune.
Source: Acerba Animi (Vatican.va)