ST. VINCENT OF LERINS I have often then inquired earnestly and attentively of very many men eminent for sanctity and learning, how and by what sure and universal rule I may be able to distinguish the truth of Catholic faith from the falsehood of heretical pravity; and I have always, and in almost every instance, received an answer to this effect: That whether I or anyone else should wish to detect the frauds and avoid the snares of heretics as they rise, and to continue sound and complete in the