15th century JMG?

[k_a_nitz]

This reminded me of a certain druid:

 

And specifically it shall be noted that if it will not manifest to one on the first night, one should not slacken until some day it may be achieved through the practice of these prayers, and one must not doubt if it does not come to pass the first time as though it could not work later on, for one should diligently persist in one’s prayers until they have been heard, and the acceptance felt. One should adhere to the process if one desires to know an answer and proceed according to the prayer and structure as it is given, because in such a way one may finally arrive at the truth. And everything rests on the diligent continuation of the prayers.

Pelagius Eremitus (d. 1480), translation from Frater Acher’s Black Abbot - White Magic p. 41.