Alleged Priscillianist Dictum of Secrecy, as recorded in Augustine, Letter 237.3

Alleged Priscillianist Dictum of Secrecy, as recorded in Augustine, Letter 237.3 

Written by Augustine to Ceretius, likely sometime after 414 CE. Section discusses an alleged dictum of the Priscillianists regarding the safe keeping of their secret doctrines. Whether this dictum goes back to Priscillian [d.385 CE], or is just held by his followers, or is indeed an invention of Augustine or other opponents of Priscillianism is unclear. For similar outlooks towards secrecy of doctrines/apocryphal works see the Oath of Justin the Gnostic, as reported in Refutation of all Heresies, 5.23-24; 5.27:1-3 (c.f. comments in the alleged Clement of Alexandria "Mar Saba Letter").

Source: Augustine, Letters, 211-270. The Works of Saint Augustine: A Translation for the 21st Century, (part 2). Trans.: Roland Teske, 2005. p. 137-138.

For some heretics could perhaps be found who are more impure, but none is comparable to them [Priscillianists] in deceitfulness. Others, of course, lie because of the habit and weakness of this life, for such vices are human, but these people are reported to have the commandment in their wicked doctrine of their heresy that, for the sake of their esoteric doctrines, they should lie even with a false oath. Those who have had experience of them and belonged to them and have been set free from them by God's mercy even quote the very words of this commandment:

"Swear, perjure yourself, but do not disclose the secret."