Which very thing, too, we observe to come from divine authority, that the priest should be chosen in the presence of the people under the eyes of all, and should be approved worthy and suitable by public judgment and testimony; as in the book of Numbers the Lord commanded Moses, saying, “Take Aaron thy brother, and Eleazar his son, and place them in the mount, in the presence of all the assembly, and strip Aaron of his garments, and put them upon Eleazar his son; and let Aaron die there, and be added to his people.” God commands a priest to be appointed in the presence of all the assembly; that is, He instructs and shows that the ordination of priests ought not to be solemnized except with the knowledge of the people standing near, that in the presence of the people either the crimes of the wicked may be disclosed, or the merits of the good may be declared, and the ordination, which shall have been examined by the suffrage and judgment of all, may be just and legitimate. And this is subsequently observed, according to divine instruction, in the Acts of the Apostles, when Peter speaks to the people of ordaining an apostle in the place of Judas. “Peter,” it says, “stood up in the midst of the disciples, and the multitude were in one place.”
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For which reason you must diligently observe and keep the practice delivered from divine tradition and apostolic observance, which is also maintained among us, and almost throughout all the provinces; that for the proper celebration of ordinations all the neighbouring bishops of the same province should assemble with that people for which a prelate is ordained. And the bishop 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 habitual conduct.
–Epistle LXVII
They are the Church who are a people united to the priest, and the flock which adheres to its pastor. Whence you ought to know that the bishop is in the Church, and the Church in the bishop; and if any one be not with the bishop, that he is not in the Church, and that those flatter themselves in vain who creep in, not having peace with God’s priests, and think that they communicate secretly with some; while the Church, which is Catholic and one, is not cut nor divided, but is indeed connected and bound together by the cement of priests who cohere with one another.
— Epistle LXVIII