Acerbo Nimis §22

²² IV. In each and every parish the society known as the Confraternity of Christian Doctrine is to be canonically established. Through this Confraternity, the pastors, especially in places where there is a scarcity of priests, will have lay helpers in the teaching of the Catechism, who will take up the work of imparting knowledge both from a zeal for the glory of God and in order to gain the numerous Indulgences granted by the Sovereign Pontiffs.