4 The question at issue is assuredly one of the highest and most serious importance. The decisions arrived at seven years ago on the school question by the Parliament of the province of Manitoba must be remembered. The Act of Union of the Confederation had secured to Catholics the right to be educated in the public schools according to their consciences; and yet this right the Parliament of Manitoba abolished by a contrary law. This is a noxious law. For our children cannot go for instruction to schools which either ignore or of set purpose combat the Catholic religion, or in which its teachings are despised and its fundamental principles repudiated. Wherever the Church has allowed this to be done, it has only been with pain and through necessity, at the same time surrounding her children with many safeguards which, nevertheless it has been too often recognized have been insufficient to cope successfully with the danger attending it. Similarly it is necessary to avoid at all costs, as most dangerous, those schools in which all beliefs are welcomed and treated as equal, as if, in what regards God and divine things, it makes no difference whether one believes rightly or wrongly, and takes up with truth or error. You know well, Venerable Brethren, that every school of this kind has been condemned by the Church, because nothing can be more harmful or better calculated to ruin the integrity of the faith and to turn aside the tender minds of the young from the way of truth.
Source: Affari Vos (Vatican.va)