Nicene and Post-Nicene Fathers, Vol. IV:
Writings in Connection with the Donatist Controversy.: Chapter 17

Chapter 17.—18.  Then he further adds:  "Both are without the life of baptism, both he who never had it at all, and he who had it but has lost it."  He therefore never had it, whom Felicianus, the follower of Maximianus or Prætextatus, baptized outside; and these men themselves have lost what once they had when, therefore, these were received with their followers, who gave to those whom they baptized what previously they did not have? and who restored to themselves what they had lost?  But they took away with them the form of baptism, but lost the veritable excellence of baptism by their wicked schism.  Why do you repudiate the form itself, which is holy at all times and all places, in the Catholics whom you have not heard, whilst you are willing to acknowledge it in the followers of Maximianus whom you have punished?

19.  But whatever he seemed to himself to say by way of accusation about the traitor Judas, I see not how it can concern us, who are not proved by them to have betrayed our trust; nor, indeed, if such treason were proved on the part of any who before our time have died in our communion, would that treason in any way defile us by whom it was disavowed, and to whom it was displeasing.  For if they themselves are not defiled by offenses condemned by themselves, and afterwards condoned, how much less can we be defiled by what we have disavowed so soon as we have heard of them!  However weighty, therefore, his invective against traditors, let him be assured that they are condemned by me in precisely the same terms.  But yet I make a distinction; for he accuses one on my side who has long been dead without having been condemned in any investigation made by me.  I point to a man adhering closely to his side, who had been condemned by him, or at least had been separated by a sacrilegious schism, and whom he received again with undiminished honor.