41 To preserve this unity of faith, all teachers of divine truths—all bishops, that is—must necessarily speak with one mind and one voice, in communion with the Roman Pontiff. "It is the union of members in the body as a whole which makes all alike healthy, all alike beautiful, and this union of the whole body requires unanimity. It calls especially for harmony among the priests. They have a common dignity, yet they have not uniform rank, for there was a distinction of power even among the blessed apostles, notwithstanding the similarity of their honorable state, and while the election of them all was equal, yet it was given to one to take the lead over the rest." (36)
Source: Aeterna Dei Sapientia (Vatican.va)