On Catholicity

St. Optatus of Milevis ca. 4th cent.

Catholicism is constituted by a simple and true understanding in the law, by an unique and most true mystery, and by unity of minds. But schism, after the bond of peace has been broken, is brought into existence through passion, is nourished by hatred, is strengthened by envy and dissensions, so that the Catholic Mother is abandoned, whilst her unfilial children go forth outside and separate themselves (as you have done) from the root of Mother Church—-cut off by the shears of their hatred—-and wickedly depart in rebellion. They are not able, however, to do anything new, or different from that which long ago they learned from their Mother. (Against the Donatists, Bk.1.11)