45 The Church of Jesus Christ has never contested the rights and the duties of the State concerning the education of its citizens; indeed, We Ourselves have recalled and proclaimed them in Our recent Encyclical Letter on the "Christian Education of Youth." Such rights and duties are unchallengeable as long as they remain within the limits of the State's proper competency, a competence which in its turn is clearly indicated and determined by the role of the State, a role which, though certainly not only bodily and material, is by its very nature limited to the natural, the terrestrial and the temporal.
Source: Non Abbiamo Bisogno (Vatican.va)