The Most Ancient Lives of Saint Patrick/The Life and Acts of St. Patrick/Chapter 193
The Light continueth for Twelve Days.
And this was the reason of the controversy. A great and wondrous light appeared, such as never in any time preceding had been beheld. Over that whole country the light continued for twelve days, without any intervention of night; for the night was illuminated, and shone even as the day. Whereby was it plainly given to be understood that the darkness of night obscured not Patrick, the son of life, the inhabiter of eternal brightness, while the night was to him the illumination of his joys, while he ascended unto the light without spot, the day without night, the sun without eclipse. And this miracle seemeth like unto that ancient miracle which was wrought by Joshua in Gibeon, though much extended in its duration. For the sun, as is written, stood still over Gibeon, and the moon stood still over the valley of Ajalon, one day for the space of two days, gave by the divine virtue the victory unto a faithful people; and by the same power the continued shining of twelve days' light showed the merit of Patrick, triumphant over this world and the prince of this world.