
Augustine of Hippo
Catena Aurea · Matthäusevangelium 7
Give not that which is holy unto the dogs, neither cast ye your pearls before swine, lest they trample them under their feet, and turn again and rend you.
(ubi sup.) The dogs are those that assault the truth; the swine we may not unsuitably take for those that despise the truth. Therefore because dogs leap forth to rend in pieces, and what they rend, suffer not to continue whole, He said, Give not that which is holy to the dogs; because they strive to the utmost of their power to destroy the truth. The swine though they do not assault by biting as dogs, yet do they defile by trampling upon, and therefore He said, Cast not your pearls before swine.