You must diligently observe and keep the practice delivered from divine tradition and apostolic observance, which is also maintained among us, and throughout almost all the provinces: that for the proper celebration of ordinations all the neighboring bishops of the same province should assemble with that people for which a prelate is ordained. And the bishops should be chosen in the presence of the people, who have most fully known the life of each one, and have looked into the doings of each one as respects his manner of life. And this also, we see, was done by you in the ordination of our colleague Sabinus; so that, by the suffrage of the whole brotherhood, and by the sentence of the bishops who had assembled in their presence, and who had written letters to you concerning him, the episcopate was conferred upon him, and hands were imposed on him in the place of Basilides. Neither can an ordination properly completed be annulled, so that Basilides, after his crimes had been discovered and his conscience made bare, even by his own confession, might go to Rome and deceive Stephen, our colleague, who was placed at a distance and was ignorant of what had been done, so as to bring it about that he might be replaced unjustly in the episcopate from which he had been justly deposed. § 51. The Unity of the Church and the See of Rome In the middle of the third century there were in sharp conflict two distinct and opposed theories of Church unity: the theory that the unity was based upon adherence to and conformity with the see of Peter; and the theory that the episcopate was itself one, and that each bishop shared equally in it. The unity was either in one see or in the less tangible unity of an order of the hierarchy. The former was the theory of the Roman bishops; the latter, the theory of Cyprian of Carthage, and possibly of a number of other ecclesiastics in North Africa and Asia Minor. Formerly polemical theology made the study of this point difficult, at least with anything like impartiality. In the passage given below from Cyprian’s treatise _On the Unity of the Catholic Church_ the text of the Jesuit Father Kirch is followed in the most difficult and interpolated chapter 4. As Father Kirch gives the text it is perfectly consistent with the theory of Cyprian as he has elsewhere stated it, and that the interpolated text is not. See, however, P. Battifol, _Primitive Catholicism_, Lond., 1911, Excursus E. Additional source material: _V. supra_, § 27; also Mirbt, §§ 56-69. The little treatise _De Aleatoribus_ (MSL, 4: 827), from which Mirbt gives an extract (n. 71), might be cited in this connection, but its force depends upon its origin. It is wholly uncertain that it was written either by a bishop of Rome or in Italy. _Cf._ Bardenhewer. Kirch also gives the text in part, n. 276; for other references, see Kirch. (_a_) Cyprian, _De Catholicæ Ecclesiæ Unitate_, 4, 5. (MSL, 4:513.)