Constantinople I: canon II

Diocesan bishops are not to intrude in churches beyond their own boundaries nor are they to confuse the churches: but in accordance with the canons, the bishop of Alexandria is to administer affairs in Egypt only; the bishops of the East are to manage the East alone (whilst safeguarding the privileges granted to the church of the Antiochenes in the Nicene canons); and the bishops of the Asian diocese are to manage only Asian affairs; and those in Pontus only the affairs of Pontus; and those in Thrace only Thracian affairs. Unless invited bishops are not to go outside their diocese to perform an ordination or any other ecclesiastical business. If the letter of the canon about dioceses is kept, it is clear that the provincial synod will manage affairs in each province, as was decreed at Nicaea. But the churches of God among barbarian peoples must be administered in accordance with the custom in force at the time of the fathers.