Nicene and Post-Nicene Fathers, Vol. IV:
Writings in Connection with the Donatist Controversy.: Chapter 1

Chapter 1.—1.  That we made a full and sufficient answer to the first part of the letter of Petilianus, which was all that we had been able to find, will be remembered by all who were able to read or hear what we replied.  But since the whole of it was afterwards found and copied by our brethren, and sent to us with the view that we should answer it as a whole, this task was one which our pen could not escape,—not that he says anything new in it, to which answer has not been already made in many ways and at various times; but still, on account of the brethren of slower comprehension, who, when they read a matter in any place, cannot always refer to everything that has been said upon the same subject, I will comply with those who urge me by all means to reply to every point, and that as though we were carrying on the discussion face to face in the form of a dialogue.  I will set down the words of his epistle under his name, and I will give the answer under my own name, as though it had all been taken down by reporters while we were debating.  And so there will be no one who can complain either that I have passed anything over, or that they have been unable to understand it for want of distinction between the parties to the discussion; at the same time that the Donatists themselves, who are unwilling to argue the question in our presence, as is shown by the letters which they have circulated among their party, may thus not fail to find the truth answering them point by point, just as though they were discussing the matter with us face to face.

2.  In the very beginning of the letter Petilianus said:  "Petilianus, a bishop, to his well-beloved brethren, fellow-priests, and deacons, appointed ministers with us throughout our diocese in the gospel, grace be to you and peace, from God our Father and from the Lord Jesus Christ."

3.  Augustin answered:  I acknowledge the apostolic greeting.  You see who you are that employ it, but see from what source you have learned what you say.  For in these terms Paul salutes the Romans, and in the same terms the Corinthians, the Galatians, the Ephesians, the Colossians, the Philippians, the Thessalonians.  What madness is it, therefore, to be unwilling to share the salvation of peace with those very Churches in whose epistles you learned its form of salutation?