39 Granted this exception, it follows that bishops who have been neither named nor confirmed by the Apostolic See, but who, on the contrary, have been elected and consecrated in defiance of its express orders, enjoy no powers of teaching or of jurisdiction since jurisdiction passes to bishops only through the Roman Pontiff as We admonished in the Encyclical Letter Mystici Corporis in the following words: ". . . As far as his own diocese is concerned each (bishop) feeds the flock entrusted to him as a true shepherd and rules it in the name of Christ. Yet in exercising this office they are not altogether independent but are subordinate to the lawful authority of the Roman Pontiff, although enjoying ordinary power of jurisdiction which they receive directly from the same Supreme Pontiff."
Source: Ad Apostolorum Principis (Vatican.va)