7 But if the pretension of excluding from public life God the Creator and Provident Ruler of that same society is impious and absurd for any people whatsoever, it is particularly repugnant to find this exclusion of God and Church from the life of the Spanish Nation, where the Church always and rightly has held the most important and most beneficially active part in legislation, in schools, and in all other private and public institutions. If such an attempt results in irreparable harm to the Christian conscience of the country, especially to its youth, whom they would educate without religion, and to families, profaned in the most sacred principles, no less harm befalls that same civil authority. When this loses the support that recommends it, nay sustains it, in the conscience of the people, namely the persuasion of its Divine origin, dependence and sanction, it loses at the same time its greatest power to obligate, and its highest title to be respected. That this inevitable damage follows a regime of separation is attested by not a few among the very nations that, after having introduced it in their regulations, very soon realized the necessity of remedying the error, either modifying, at least in their interpretation and application, the laws persecuting the Church, or endeavoring, in spite of separation, to come to a pacific plan of coexistence and cooperation with the Church.
Source: Dilectissima Nobis (Vatican.va)