The Truth make us free. I think that it is not difficult knowing what is the truth religion if it is sought with good will and we don´t put obstacles to the Grace. That is what the spaniards we have defended always in our History since the Third Council of Toledo (589 A.D.).

You can start with the Cathecism of the Coucil of Trent, the Cathecism of St. Pius X and the Encyclicals and other Papal documents (better of the Popes Leo XIII, St. Pius X, Pius XI and Venerable Pius XII).

In Christ.