The Canons of the Synods of Sardica, Carthage, Constantinople, and Carthage Under St. Cyprian, Which Canons Were Received by the Council in Trullo and Ratified by II. Nice 146Canon CXXIII.

That if a bishop neglects his diocese he is to be deprived of communion.

If in the mother cathedrals a bishop should have been negligent against the heretics, let a meeting be held of the neighbouring diligent bishops, and let his negligence be pointed out to him, so that he can have no excuse. But if within six months after this meeting, if an execution was in his own province, and he had taken no care to convert them to Catholic unity, no one shall communicate with him till he does his duty. But if no executor shall have come to the places, then the fault shall not be laid to the bishop.