Nicene and Post-Nicene Fathers: Series I/Volume IV/Donatist Controversy/On Baptism/Book VII/Chapter 33
Chapter 33.—64. Donatulus of Capse[1] said: "I also have always entertained this opinion, that heretics, who have gained nothing outside the Church, should be baptized when they are converted to the Church."[2]
65. To this the answer is: They have, indeed, gained nothing outside the Church, but that is nothing towards salvation, not nothing towards the sacrament. For salvation is peculiar to the good; but the sacraments are common to the good and bad alike.