Pascendi Dominici Gregis §54

⁵⁴ We have already mentioned congresses and public gatherings as among the means used by the Modernists to propagate and defend their opinions. In the future Bishops shall not permit Congresses of priests except on very rare occasions. When they do permit them it shall only be on condition that matters appertaining to the Bishops or the Apostolic See be not treated in them, and that no motions or postulates be allowed that would imply a usurpation of sacred authority, and that no mention be made in them of Modernism, presbyterianism, or laicism. At Congresses of this kind, which can only be held after permission in writing has been obtained in due time and for each case, it shall not be lawful for priests of other dioceses to take part without the written permission of their Ordinary. Further no priest must lose sight of the solemn recommendation of Leo XIII.: Let priests hold as sacred the authority of their pastors, let them take it for certain that the sacerdotal ministry, if not exercised under the guidance of the Bishops, can never be either holy, or very fruitful or respectable (Lett. Encyc. Nobilissima Gallorum , 10 Feb., 1884).